Apparatus and method responsive to the on-board measuring of the load carried by a truck body

ABSTRACT

The invention relates to an apparatus for accurately measuring the weight of a load carried by a truck body which is mounted on a truck frame. The apparatus is located along an interface between the truck frame with the load carried by the truck body and uniformly distributes the weight of the body onto the frame along the interface. In order to measure the weight of the load, the apparatus includes pressure sensors which communicate the entire weight of the load to the truck frame. The pressure sensors provide an electrical signal proportional to the pressure exerted by the load on the apparatus. This electrical signal is processed to calculate the weight of the load carried in the truck body. By providing a pressure sensing apparatus at an interface between the load and truck frame, the weight on the load carried by the truck body can be continually monitored without interrupting the loading, hauling and dumping routine. A sensor processing unit responds to the continually monitored weight data and the like to provide hauling parameters to track the performance of the truck and to provide a data base to a central computer from which data can be gathered for efficiently controlling the movement of a plurality of trucks.

This application is a continuation-in-part application of U.S. Ser. No.604,739 filed 4-27-84, now U.S. Pat. No. 4,630,227.

TECHNICAL FIELD

The invention generally relates to the measuring of the load of avehicle and, more particularly, to the measuring and acquisition of dataindicative of loading conditions for a hauling vehicle.

BACKGROUND

Often off-road trucks are subjected during their routine use to weightloads which differ greatly because of different material density and/orthe ability of some material to more tightly pack when loaded into thetruck body. As a result, truck bodies which are always filled to theirfull volume capacity may carry weight loads which exceed the weightcapacity of the truck. Repeated occurrences of overloading result in thepremature deterioration of the structural integrity of the truck, thusrequiring repair or replacement of parts before anticipated. In order toavoid the damage caused by overloading, the truck body can be filled toa volume which assures the truck is not overloaded even for the mostdense material. Although underloading may prevent the prematuredeterioration of the structural integrity of the truck, it sacrificesthe truck's load-hauling efficiency. Therefore, an off-road truck whichis expensive to operate becomes even more expensive to operate when itis underloaded. Accordingly, there is a need to precisely measure theload carried by an off-road truck. This need has stimulated thedevelopment of on-board weighing devices that monitor and measure thetruck's load.

Of course, in order to measure the on-board weight of a load carried bya truck, the truck must necessarily incorporate load sensors into itsframe and/or body. In a dump-body truck, the body is movable on thetruck's frame between lowered and raised positions. To provide for thismovement, the body is usually attached to the frame only by a pair ofhinge assemblies and a pair of hydraulic cylinders. In one commonconstruction of a dump-body truck, when the truck body is in its loweredposition, its entire weight is communicated to the truck frame along acushioned interface between the truck's frame and body. In this loweredposition of the truck body, the hinge assemblies and hydraulic cylindersdo not support the weight of the truck body and, therefore, they do nottransfer any of the body's weight to the truck frame. By freeing thehinge assemblies and the hydraulic cylinders from the weight of thelowered truck body, the amount of stress on these areas is reduced and,accordingly, their useful life is extended.

Traditionally, in order to provide an on-board weighing device for thistype of a dump-body truck, load sensors are incorporated into the hingeassemblies and the hydraulic cylinders. Accordingly, in order to measurethe load, the truck body must be lifted from its lowered position by thehydraulic cylinders so that the weight of the load is transferred to theframe through the cylinders and the hinge assemblies. Although theaccuracy of the load measurements obtained from load sensors associatedwith the hydraulic cylinders and the hinge assemblies is satisfactory,the structural integrity of the truck may be degraded by modificationsof the hinge assemblies and hydraulic cylinders required to incorporatethe load sensors which cause concentration of the load on the frame.Moreover, the impact of falling material onto the bed of the truck isespecially severe for the frame of the truck when the body is liftedslightly from its lowered position.

More important than the structural disadvantage of on-board weighingdevices which incorporate load sensors in the truck's hinge assembliesand hydraulic cylinders is the disadvantage of requiring the truck'sbody to be lifted off the frame in order to obtain a weight reading.Because this requirement consumes valuable time otherwise available forloading, hauling, and unloading and because of the concentration of theload on the frame, the truck operator is discouraged from weighing thetruck load; it is faster to approximate the load. Since the on-boardweighing device interferes with an efficient and smooth haulingoperation, there is a tendency to not use the weighing device.Therefore, the advantages of an on-board weighing devices in dump-bodytrucks have not been fully realized. Also, the requirement of liftingthe truck body off the frame in order to obtain a weight measurementprevents continuous or periodic monitoring of the body's weight.

In order to continuously monitor and measure the load carried by adump-body truck, it is known to use pressure gauges or similar type loadsensors in the truck's suspension. Usually, in these types of weighingdevices, the fluid pressure within a hydraulic suspension cylinder issensed. Because of the relatively short stroke of the cylinder and therelatively large amount of frictional resistance to the cylinder'smovement (the front cylinders normally also serve as the front axlespindles), the pressure reading is not a satisfactorily accurateindication of the truck's weight. In addition, the modification of thetruck's suspension to include load sensors opens the possibility ofdangerously degrading the suspension system.

SUMMARY OF THE INVENTION

It is the general object of the invention to provide an apparatus andmethod for accurately measuring loading and hauling parameters based onthe weight of material carried by a truck body. In this connection, itis a object of the invention to reliably measure and record loading andhauling parameters of the truck body in order to increase the efficiencyof loading and hauling and also to provide a permanent record of truckuse and the conditions under which it operated.

It is an important object of the invention to provide an apparatus andmethod for measuring and indicating locating and hauling parameters ofthe truck body in order to provide an archive indicative of the type anddegrees of use the truck has experienced.

It is another object of the invention to extend the usable life of adump-body truck by using loading and hauling parameters to prevent theunnecessary deterioration of the structural integrity of the truckresulting from weight overloading.

It is a further object of the invention to eliminate the inefficienthauling of loads by a dump-body truck which results from theunder-utilization of the full weight capacity of the truck.

Other objects and advantages of the invention will be apparent from thefollowing detailed description and the accompanying drawings.

Briefly, in accordance with the invention, an on-board weighing deviceis provided for a dump-body vehicle which continuously monitors theweight of the body while it is in its lowered position on the frame ofthe vehicle. In its lowered position, the body rests on the on-boardweighing device such that the device forms an interface between the bodyand frame of the vehicle. A sensor processing unit mounted on thevehicle is responsive to signals from the on-board weighing device whichare indicative of the weight of the body. From the load signals of theon-board weighing device, the sensor processing unit forms a data basefrom which the vehicle's hauling performance is measured. In addition,load signals from the on-board weighing device are processed by thesensor processing unit and the resulting data is transmitted from eachvehicle to a central processor wherein a second data base is formed.From this second data base, the central processor transmits controlsignals to selected vehicles in order to control the movement of thevehicles between load and dump sites.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an elevated perspective view of a dump-body truck with thetruck body in a raised or dump position so as to expose the on-boardweighing device according to the preferred embodiment of the invention;

FIG. 2 is an enlarged elevated perspective view of the dump-body truckin FIG. 1 that more clearly shows the on-board weighing device accordingto the preferred embodiment of the invention;

FIG. 2a is an exploded perspective view of a truck having a stationarybody and supported on a frame incorporating the on-board weighing deviceaccording to the invention;

FIG. 2b is a systems diagram of an on-board system according to theinvention for monitoring, storing and analyzing truck parameters whichincludes the on-board weighing device as well as other sensor inputs;

FIG. 3 is a cross-sectional view of one of the truck body hingeassemblies joining the truck body and frame, taken along the line 3--3in FIG. 2 and showing three alternative pivot pin assemblies offered byvarious truck manufacturers;

FIG. 3a is a sectional view of the truck hinge assembly taken along theline 3a--3a in FIG. 3 and showing a suggested modification to one of thepivot pin assemblies of FIG. 3 in order to make the hinge assembly"free-floating";

FIG. 4 is a side view of the preferred embodiment of the on-boardweighing device according to the invention, taken substantially alongthe line 4--4 in FIG. 2;

FIG. 5 is a front view of the on-board weighing device according to afirst alternative embodiment of the invention, taken along the line 5--5in FIG. 4;

FIG. 5a is a front view of a second alternative embodiment for theon-board weighing device according to the invention, taken along theline 5--5 in FIG. 4;

FIG. 6 is a front view of the preferred embodiment for the on-boardweighing device according to the invention, taken along the line 5--5 inFIG. 4;

FIG. 7 is a cross-sectional view of the preferred embodiment for theon-board weighing device according to the invention, taken along theline 7--7 in FIG. 4;

FIG. 7a is an enlarged partial side view of the on-board weighing devicetaken along the line 7a--7a in FIG. 7 showing details of the means forsecuring the device to the truck frame;

FIG. 8 is a plan view of a clamping subassembly of the on-board weighingdevice;

FIG. 8a is an exploded end view of a clamp portion of the clampingsubassembly, taken along the line 8a--8a in FIG. 8;

FIG. 9 is a cross-sectional view of the clamping subassembly in FIG. 8,taken along the line 9--9 and showing a side view of a collar portion ofthe subassembly;

FIG. 10 is a side view taken along the line 4--4 in FIG. 2 showing afirst alternative embodiment of the on-board weighing device accordingto the invention;

FIG. 11 is an end view of the first alternative embodiment of theon-board weighing device, taken along the line 11--11 in FIG. 10;

FIG. 12 is a side view taken along the line 4--4 in FIG. 2 showing asecond alternative embodiment of the on-board weighing device accordingto the invention;

FIG. 13a is a side view of a heavy duty, off-road truck illustrating therelative dimensions of the truck used by the on-board weighing device ofthe invention to measure front and rear axial loads;

FIG. 13b is a side view of the heavy duty, off-road truck of FIG. 13awith the truck body slightly raised by the hoist cylinders in order forthe on-board weighing device to complete a determination of front andrear axial loads;

FIGS. 14a and 14b are side views of a scraper vehicle in its raised andlowered positions, respectively, illustrating the relative dimensionsused to estimate front and rear axial loads;

FIGS. 14c and 14d are partially side views of the scraper vehicle inFIGS. 14a and b, respectively, illustrating the relative positions ofthe vehicle's hoist cylinder and associated mechanisms;

FIGS. 15a and 15b are plan and side views, respectively, for a platformscale incorporating the on-board weighing device of the invention;

FIG. 16 is a block diagram of the electronic system which receivessignals from the on-board weighing device according to the invention;

FIG. 16a is a schematic diagram of the temporary memory used inconnection with the electronic system of FIG. 16;

FIG. 17a is a plan view of a mechanical processing system for receivingsignals from the on-board weighing device in lieu of the electronicsystem of FIG. 16;

FIG. 17b is a cross-sectional view of the mechanical processing systemtaken along the lines 17b--17b in FIG. 17a;

FIG. 17c is a perspective view of the piston subassembly of themechanical processing system;

FIGS. 18a-f, h-k, m, p and r are flowchart diagrams for the softwareutilized in connection with the electronic system of FIG. 14;

FIGS. 19a and 19b are schematic diagrams illustrating a truckdistribution system utilizing the weight data received from the on-boardweighing device of the invention;

FIG. 19c is a enlarged, partial sectional view of the truck body showingan alternative embodiment for sensing the presence of a load for use inconnection with the truck distribution system of FIGS. 19a and 19b; and

FIGS. 20a and 20b are flowchart diagrams for the software of the centralcomputer and truck, respectively, utilized in connection with the truckdistribution system of FIGS. 19a and 19b.

While the invention will be described in connection with a preferredembodiment and certain alternative embodiments, it will be understoodthat it is not intended to limit the invention to those particularembodiments. On the contrary, it is intended to cover all alternativesand equivalents as may be included within the spirit and scope of theinvention as defined by the appended claims.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Turning to the drawings, and referring first to FIG. 1, an exemplaryoff-road truck 11 includes a truck body 13 which is hinged to the truckframe 15 at hinge assemblies 17. By controlling the extension oftelescoping hydraulic cylinders 19 and 21, the truck body 13 is pivotedbetween a fully inclined or dump position and a lowered or restposition. One end of each hydraulic cylinder 19 and 21 is fastened to ahinge assembly located on the bottom of the truck body 13. The opposingend of each cylinder 19 and 21 is fastened to an articulation on thetruck frame 15. Structurally, the truck body 13 consists of steel panels23, which form the shape of the body, and beams 25 which provide thebody's structural framework. Since other dump-body trucks may also usethe on-board weighing device of this invention, the truck in FIG. 1 isintended as an exemplary truck frame and truck body utilized inconnection with the invention.

Often, off-road trucks, such as the one shown in FIG. 1, are very large.For instance, it is not uncommon for the truck's tire diameter to be asgreat as the height of an average man. Accordingly, the tremendous sizeof these trucks makes them expensive to operate and repair. Since thesetrucks represent both a large capital investment and a large operatingexpense, preventing both overloading of the truck body andunder-utilization of the truck's load capacity (i.e., underloading) areimportant considerations in insuring the truck is operated in the mostprofitable manner. In particular, if the truck is overloaded it willtend to have a shorter usable life because of the excessive wear causedby the overloading. On the other hand, if the truck is underloaded, thetruck must be operated over a longer period of time, thereby consumingmore fuel and wearing the truck's parts to a greater degree. Therefore,the ability to accurately measure the truck's load is important to theefficient operation of large off-road trucks. Also, since theseoff-road, heavy duty trucks are extremely expensive to operate, loadingand hauling parameters indicative of truck performance can be of greateconomic value by using the parameters to discover areas of theperformance which may be improved.

Typically, a shovel or front-end loader is used to fill the truck body.With a front-end loader, material is loaded into the truck body 13 by abucket located at the end of an arm of the loader wherein the armcontrols the movement of the bucket. Typically, the truck body has aweight and volume capacity such that a plurality of loaded buckets mustdump material into the truck body 13. Even though the operator of thefront-end loader is at an elevated level when operating the loader, heor she may not be in a position to see over the edge of the truck bodyto determine the level of loading. Consequently, it is difficult toexactly control the amount of material loaded into the truck body.Moreover, the density of the material loaded into the truck body oftenvaries over a significant range; therefore, even if it is possible toaccurately determine a certain level of loading, a particular level isonly a reliable indication of a weight limit when the material ishomogeneous and its density is known.

As most clearly shown in FIG. 2 the truck frame 15 is composed of twoparallel beams 26 and 27 connected by transverse beams (not shown) toform a support surface for the truck body 13 over the rear axle of thetruck. In order to provide a pivot axis for the truck body 13, each ofthe hinge assemblies 17 integrally connects one end of each of theparallel beams 26 and 27 to one of beams 28 and 29 on the underside ofthe truck body. In its lowered position, the beams 28 and 29 of thetruck body 13 mate with the beams 26 and 27 of the truck frame 15. Aswill be more fully explained hereinafter, when the truck body 13 is inits lowered position, the entire weight of the truck body and its loadis transferred to the truck frame 15 by way of the interface between thebeams 26 and 27 of the frame and the beams 28 and 29 of the body. Asmentioned above, trucks are different design than that shown as anexemplary embodiment may use the invention. Some truck designs havebeams 26 and 27 which are angled with respect to the ground. These typesof trucks may also be equipped with the invention if suitableprecautions are taken against slippage of the apparatus on the beams andto ensure proper calibration.

Each of the hinge assemblies 17 includes first and second complementaryhinge members 30 and 31 which are secured to the frame 15 and body 13,respectively, and interconnected by a pivot pin 32. The hydrauliccylinders 19 and 21 and the truck body 13 are interconnected by hingeassemblies 33. (Only one of the hinge assemblies 33 can be seen in theview of FIGS. 1 and 2). Hoist pins 35 interconnect the complimentaryhinge members 37 and 39 of the hinge assemblies 33. Although, as thecylinders extend, the hinge assemblies 33 accommodate the relativerepositioning between the hydraulic cylinders 19 and 21 and the truckbody 13, articulating assemblies 41 (only one is shown in FIGS. 1 and2), which connect the cylinders to the truck frame 15, allow a similarrelative repositioning between the hydraulic cylinders and the truckframe 15.

Ordinarily, cushioning suport materials such as rubber pads (not shown)are added along the length of the two parallel beams 26 and 27 of thetruck frame 15 so when the truck body 13 is in its lowered position thematerial provides a cushioned interface between the beams 28 and 29 ofthe truck body and the beams 26 and 27 of the truck frame. In order toevenly distribute the weight of the truck body 13 along the length ofthe frame 15 and thereby provide the best possible weight distributionfor the frame, the cushioning support material is characterized by athickness dimension which, as explained hereinafter, cooperates with thehinge assemblies 17 when the truck body is moved to its loweredposition. The cooperation of the cushioning support material and thehinge assemblies 17 frees the assemblies from supporting any of thetruck body's weight when the body is in its lowered position.

Referring to FIG. 4, in accordance with the invention, the cushioningsupport materials mounted by the manufacturer on the parallel beams 26and 27 of the truck frame 15 are replaced by lengths of fluid-filledtubings 47 that are laid along the lengths of the parallel beams toprovide, when combined with pressure sensors, an on-board weighingdevice which accurately measures the weight of the truck body 13 whileit is in its lowered position. Each of the tubings 47 is capped by aninverted U-shaped metallic shield 49 to protect the tubing at itsinterface with the truck body 13. The inverted U-shaped shields whichprotect the tubing are free to move vertically on the parallel beams 26and 27. As illustratedin FIG. 4, each of the fluid-filled tubings 47 isdivided into fore and aft sections which may either be created byclamping the center of one long tubing or providing two separatesections of tubing. At the ends of each of the fluid-filled tubings 47are pressure sensors 51a-d which measure the liquid pressure within thetubing (which may be remote mounted).

Because the on-board weighing device offers a reliable indication of theweight of a dump body while the body is in its lowered or restingposition, weight data may be accurately and continuously monitored andprocessed. Applicant believes such an ability was previously unavailablefor dump-body trucks. Based on this ability, the on-board weighingdevice provides vehicle information features which, to the best ofapplicant's knowledge, were previously unavailable. Limited only by thesensitivity of the sensors used as the pressure sensors 51, the on-boardweighing device may provide a highly accurate indication (e.g., 0.25% or0.5% error) of the load carried by an off-road, heavy-duty truck. Anexample of a particular pressure transducer which may be used for thepressure sensors 51 is the Heise Series 620 Pressure Transducer,manufactured by the Instruments Division of Dresser Industries, Newton,Conn. Another example of a pressure sensor suitable for use inconnection with the invention is the AMETEK LVDT pressure transducer,manufactured by Ametek of Sellersville, Pa. The following paragraphscharacterize the general and particular aspects of the invention whichare described in detail in later sections of this description.

Referring to FIG. 2a, a fixed body 13' fitted to the frame 15 of thetruck 11 may also utilize the on-board weighing system of the invention.The particular means for coupling the frame 15 to the body 13' in FIG.2a allows the full weight of the body to rest upon the tubings 47. Thecoupling means, pins 160 supported by cross members 162 of the frame 15and cooperating bores 164 in cross members 166, prevent fore-and-aft orside-to-side movement of the body relative to the frame while, at thesame time, allowing free vertical movement of the body 13'. In order toprevent the body 13' from accidentally freeing itself from the body bybouncing high off the frame, a cotter pin or similar retainer means 168is secured at the top of the pins 160 in order to limit the verticalmovement of the body. As indicated by FIG. 2a, the stationary truck body13' may in style be a dump-body, (the leftmost portion of the body 13'),a flatbed body (the rightmost portion of the body 13'), or it may beother known body types which suitably function as stationary bodies.

Referring to FIG. 2b, in addition, the on-board weighing device includesa processor means 101 responsive to signals from the sensor 51a-d. Byproviding an on-board processing means, the raw pressure data from theon-board weighing device can be monitored and converted to useful weightinformation for the real-time control of the truck by the operator. As acomplement to the pressure data, the on-board system illustrated in FIG.2b includes other input data source with provide raw data to theprocessor means 101. As will be explained more fully hereinafter, usefuloperator information is supplied via outputs from the processor means101 in response to the pressure data from the on-board weighing deviceand its complementary sensors.

The complementary systems in ths system include, but are not limited to,a hoist cylinder pressure gauge 139, a distance sensor 138, aforward-neutral-reverse (F-N-R) switch 135 and a dump switch 137. Akeypad 122 is used by the operator to request data and to enter anoperator number which identifies himself to the system. Examples ofother possible complementary input devices are fuel consumption flowmeters and slope transducers for detecting the pitch or grade of theroad.

Various on-board outputs controlled by the processor means 101 providethe truck operator with indications of truck operating conditions inresponse to the raw data from the on-board weighing device andcomplementary sensors. Specifically, a printer 119 provides a hard copyoutput for analysis by the truck operator or management personnel. Anaudio output 196 alerts the operator to situations requiring immediateattention. Similarly, display 197 tells the operator of a load imbalancewhich requires correction. In order to provide the operator withnon-permanent data information, such as current weight, a digitaldispaly 117 is provided. Stacked lights 140 are preferably mounted onthe side of the truck in order to give the operator of the loaderequipment an idea of the remaining capacity in the truck. Finally, atransceiver 150 is provided in order to download accumulated data to aremote site for construction of historical files. The cooperation andinteraction of the foregoing inputs and outputs in FIG. 2b will be setforth in detail hereinafter. Before proceeding to the specificdescription of this cooperation and interaction, a summarized overviewwill be presented. Following this, descriptions of subassemblies for theon-board weighing device will be described in detail and alternativeembodiments of the device will be briefly mentioned before proceeding toa detailed discussion of data manipulation.

In accordance with the invention, an apparatus for processing dataderived from the weight of the load carried by the body of a truckincludes a processor means 101 for receiving data from the pressuresensors 51 and, in response thereto, detecting a change in the weight ofthe truck body and formulating data indicative of truck condition inresponse to changes in pressure data from the pressure sensors. Pressuredata and indications of changes in the data are used by the processingmeans 101 to establish a data base from which various truck parametersmay be monitored either by the processor means or by a remote stationaryprocessor (not shown) radio linked to the on-board processor by way oftransceiver 150.

In accordance with one particular aspect of the invention, the processormeans 101 cooperates with the on-board weighing device for determiningthe average weight of the material carried by a bucket of a front-endloader and displaying information to the truck or loader operator on thestacked display 140 indicative of whether another full bucket can beloaded into the truck body 13 without overloading the truck. If anotherfull bucket cannot be loaded into the truck, a display indicates to thetruck or loader operator the fraction of a loaded bucket which can besafely added to the truck body. By providing the foregoing means andfunctions, the truck 11 can be safely and regularly loaded to itsmaximum hauling weight without risking damage to the truck by exceedingits weight limit.

In connection with the foregoing, the processor means includes means fordetecting an overload condition by comparing the actual weight of thetruck body with a predetermined maximum weight. If the weight of thetruck body exceeds the predetermined maximum weight, an overloadcondition is recorded and indicated to the truck operator on digitaldisplay 117.

In accordance with another particular aspect of the invention, theon-board weighing device cooperates with a pressure sensor 139 in thehydraulic line of the hydraulic cylinders 19 and/or 21 to provide datato the processor means 101 for establishing the relative weightdistribution of the truck body over the front and rear axles. Theprocessor means 101 processes the pressure readings from the on-boardweighing device and pressure readings from the sensor 139 of thehydraulic cylinders 19 and/or 21 in order to provide the truck operatorwith accurate values for front and rear axle loads.

In accordance with yet another particular aspect of the invention, theon-board weighing device includes means for providing a plurality ofpressure readings fore and aft of the truck body 13, and, in addition,side to side of the truck body. The processor means 101 compares thefore and aft or side-to-side distributions of load in order to warn thetruck operator at display 197 or audio output 196 of imbalancedconditions which may harm the truck.

In accordance with still another particular aspect of the invention, theon-board weighing device cooperates with distance sensor 138 to providedata to the processor means 101 in order to give an indication of tirewear in units of tons.miles/hour which is commonly used in the heavyduty truck industry as an indication of the loading capability of thetire. This unit of measurement has been established as a maximum tireloading and is indicative of tire wear for tires of heavy duty, off-roadtrucks. Tire wear is important since, for many truck users, the highesthourly operating cost after the operator himself is the cost of tirereplacement. For each haul cycle segment (i.e., load to dump site orvice versa), the processor means (1) reads the pressure reading from theon-board weighing device which corresponds to the weight of the body 13and adds to that weight the known weight of the truck, (2) reads thehauling distance of the truck 11 from the distance sensor 138 and (3)reads the hauling time of the truck. This collected data is downloadedto a remote central station for calculation of ton.mile per hour fordisplay to management personnel. In a related aspect of the invention,the processor means is responsive to the pressure data from the on-boardweighing device and the data from the distance sensor to provide anindication of truck movement when the body is not fully lowered on thetruck frame and also to provide an indication of a "haul-backcondition", i.e., a partial load remaining in the body after a dump hasbeen completed.

In accordance with another particular aspect of the invention, theprocessor means 101 includes means for processing and storing haulingdata derived from the on-board weighing device in order to catalog andrecord important parameters of truck and operator performance. Byidentifying each operator and/or down-time status, (e.g., operator onbreak, truck in shop for maintenance) by unique identification numbers,data generated while a particular operator is controlling the truck orwhile the truck is in a particular down-time status may be recorded andcataloged by the processor means. Operator data is stored in a memorymeans until they are called for by the operator through keypad 122. Whencalled, the processor means organizes the data into a displayed/printedsummary.

In accordance with another particular aspect of the invention, theprocessor means 101 includes means for determining the degree ofroughness of the road traveled by the truck 11 by identifying pressurespikes measured by the on-board weighing device. Because excessivelyrough roads can affect the efficiency of hauling and, more importantly,substantially damage the trucks, the degree of roughness of the roadstraveled by the truck 11 is an important parameter.

In accordance with another particular aspect of the invention, a centralcomputer is provided having a signal link with each of the processorsmeans 101 on-board the off-road, heavy duty trucks. Data transmittedfrom each of the processor means by way of transceiver 150 to thecentral computer is processed by it and instruction data is returned toeach processor means. Specifically, a data base is developed by thecentral computer from data downloaded from the processor means 101 ofall the trucks whereby the central computer monitors and controls truckmovement. For example, conclusions reached from the downloaded data, areused by the central computer to route the trucks to load and dump sitesmost efficiently and/or to control the type of load delivered to aparticular dump site.

Finally, in accordance with another particular aspect of the invention,the foregoing features provided by the processor means in response todata from the on-board weighing device and accessory devices mounted onthe truck are also realized for an off-road scraper vehicle or for astationary platform scale. For a scraper vehicle, pressure dataindicative of material load is provided to an on-board processor meansfor generating a data base from which total load and load distributioncan be estimated. For a platform scale, the on-board weighing device ismodified to provide the essential pressure data required by theprocessor means to establish a data base from which total load can bedetermined.

Turning now to specific subassemblies of the on-board weighing deviceand also several alternative embodiments of the device, FIG. 3illustrates three alternative embodiments in one cross-sectional view inorder to show common hinge assembly configurations offered by varioustruck manufacturers. Referring specifically to the center embodiment inFIG. 3, in order to free the hinge assemblies 17 from the weight of thetruck's load when the truck body is moved to its lowered position,oversized bores 43 of the hinge members 30 (the bores receive the bodypivot pins 32) allow the hinge members 31 to lift the pivot pins 32 intoa position which disengages the hinge member 30 from the hinge members31. By providing the cushioning support material with a thicknessdimension greater than the distance from the lowermost portion of thebeams 28, 29 to the beams 26 and 27 when the beams are parallel, theengagement of the truck body with the cushioning support material causesthe pivot pins 32 securely held by the bores 44 in the hinge members 31,to be lifted off the lower surfaces of the bores. Also, as is well knownin the art, when the truck body 13 is moved to its lowered position andthe telescoping cylinders 19 and 21 are fully collapsed, the hydrauliccylinders are released to a float position.

Accordingly, when the truck body 13 is moved to its lowered position,the entire weight of the truck body is transferred from the hingeassemblies 17 and hydraulic cylinders 19 and 21 to the body-frameinterface provided by the cushioning support material between the beams26, 27 and the beams 28, 29, wherein the latter are in parallel with theformer. It will be appreciated that this cushioning support material isprovided by the truck manufacturer in order to (1) cushion the matingsurfaces between the beams 28, 29 of the truck body 13 and the beams 26,27 of the truck frame 15, (2) provide a surface which lifts the truck'sweight off the hinge assemblies 17 when the body is moved to its loweredposition, thereby evenly distributing the truck's load along the lengthof the frame 15 and (3) allow for variations in parallelness betweenbeams 26, 27 and beams 28, 29. As illustrated by the righthandembodiment of the hinge assembly in FIG. 3, the oversized bores 43' ofthe hinge members 30 may be lined with a rubber-like material 45 and asheathing 45a in order to dampen any excessive movement of the pivotpins 32 in the oversized bore and protect the wall of the bore fromdamage.

Because the thickness of the assembly comprising the fluid-filledtubings 47 and the metallic shields 49 is equal to the thickness of thecushioning material that they replace, the pivot pins 32 are lifted offthe lowermost portion of the bores 43 when the truck body is moved toits lowered position. Accordingly, when the truck body 13 is loweredonto the parallel beams 26 and 27 of the truck frame, the entire weightof the truck body 13 and its load is transferred to the truck frame 15by way of the interface provided by the fluid-filled tubings 47. As aresult of the fluid-filled tubings 47 supporting the entire weight ofthe truck body 13 in its lowered position, an increase in liquidpressure sensed by the pressure sensors 51 which accurately representsthe total weight of the truck body. Not only do the fluid-filled tubings47 provide a mechanism for measuring the total weight of the loadcarried by the truck body, they also provide the cushioned supportbetween the truck body 13 and the truck frame 15 previously provided bythe truck manufacturer's cushioning support material.

Generally, the tubings 47 should be composed of material that isresistant to penetration by oil (oil is the most preferred liquid forfilling the tubings). More importantly, the tubings 47 must not besusceptible to permanent deformation from the weight of the truck body13. In particular, the tubings 47 should not include any type of braidedwire that might permanently deform under external pressure. An exampleof a tubing suitable for use in connection with the invention is theJAFIB fire hose manufactured by the Jaffrey Fire Protection Company,Inc. of New Hampshire. For any particular choice of hose, it must bewear and abrasion resistant. A modified fire hose may be used; anexample of a preferred modified fire hose is a three-ply urethane firehose (i.e., concentric layers of urethane, fiber and urethane) with anadded inner lining of hose fiber with the fiber's inner diameter coveredwith a sealing material such as rubber.

It will be appreciated by those familar with off-road trucks that somemanufacturers provide a cushioning support material between the truckbody 13 and truck frame 15, but they do not provide a means to free thehinge assemblies 17 from supporting a portion of the weight of the truckbody when in a lowered position. Such a hinge assembly is shown by theleftmost embodiment in FIG. 3 wherein the pivot pin 32 fits snuglywithin the bore 43". In accordance with the invention, these types oftrucks may be modified to allow all the weight of the body to besupported along the body-frame interface by machining small crescentprofiles off the tops of the pivot pins 32 such that the profile of thepins is egg shaped. As illustrated by the modified pin 32 in FIG. 3a,this modification allows the hinge members 30 and 31 to disengage whenthe truck body is lowered onto the tubings 47, thereby enabling thepressure sensors 51 to measure the pressure from the full weight of thetruck body.

In order to calibrate the fluid-filled tubings 47 which support thetruck body 13 in its lowered position over the truck frame 15, a liquid(e.g., oil) of relatively low viscosity is pumped into the tubings whilethe empty truck body is resting on the tubings, i.e., in its loweredposition. Relatively low viscosity is chosen in order to ensure properflow during winter temperatures. The pumping of the liquid is stoppedwhen the beams 28 and 29 of the truck body 13 are parallel to the beams26 and 27 of the frame 15. At this point there is still a slight amountof contact between the pvot pins 32 and the lower portions of the bores43 in the hinge members 30. Therefore, there is still a slight amount ofbody weight supported on the frame 15 through the hinge assemblies 17.In order to lift the pivot pins 32 off the hinge members 30, additionalliquid is pumped into the tubings 47 until the pivot pins 32 arevisually lifted off the lowermost portions of the bores 43. Althoughthere is some downward vertical movement of the inverted U-shapedmetallic shields 49 as the truck body 13 is loaded, the movement is notsufficient to cause the pivot pins 32 to re-engage the bores 43 of thehinge members 30.

At each pressure sensor 51a-d associated with the fluid-filled tubings47, the liquid pressure is converted to an electrical potential which isdelivered to electrical circuitry, discussed hereinafter, to calculate aweight measurement. Referring to FIG. 4, each of the fluid-filledtubings 47 is preferably cut at its central area in order to provide twoseparate fluid-filled chambers. By cutting the tubings 47, each pressuresensor 51a-d at an end of a tubing 47 supplies the electronic circuitrywith an independent pressure reading. By dividing each tubing 47 intotwo chambers, the corresponding four pressure readings can bemanipulated to provide an indication of the weight distribution of theload, e.g., too much weight fore, aft or side to side as will bediscussed in greater detail hereinafter.

In alternative configurations of the tubings, each tube can be a unitarypiece such as schematically shown in FIG. 5 or it may consist of aplurality of tubings of smaller cross-section as shown in FIG. 5a (thesesmaller tubes may be within a larger tube). Referring to FIG. 6, inorder to provide an easily ascertainable amount of contact area betweenthe fluid-filled tubings 47 and the shields 49, a contact plate 60 issecured to the bottom of the channel formed by the shields in thepreferred embodiment of the invention. The tubings 47 are filled withfluid so as to provide a contact surface along the entirecross-sectional length of the plate 60. Also, the tubings 47 are freefrom contacting the side walls of the shields 49. By the tubings 47 onlycontacting the bottom surface of plate 60, the weight can be accuratelydetermined, i.e., pressure×area=weight.

Turning to FIG. 7, a more detailed cross-section of the apparatuscomprising the on-board weighing device is shown. A subassembly,comprised of welded portions 61a, 61b and 61c illustrated in FIG. 7, isprovided for securing the on-board weighing device to each of the beams26 and 27. The subassembly fits over each of the beams (beam 27 is shownin FIG. 7). In order to secure the subassembly on the beam 27, a flatplate 62 is butted against the lower surface of the beam 27 and fastenedto the portions 61a and 61b of the subassembly by way of nuts and bolts63a and 63b, respectively. Referring to FIG. 7a in conjunction with FIG.7, outrigger pairs 64a and 64b are secured to the shield 49. Fittedbetween the pairs of outriggers 64a and 64b are bolt assemblies 190a and190b, respectively, which are secured to side portions 61a and 61b,respectively. Because of rods 191a and 191b extending between theoutrigger pairs 64a and 64b, respectively, the shield 49 is restrainedfrom accidently coming free from its position over the tubings 47.Upward movement of the shield 49 and the integrally attached outriggerpairs 64a and 64b will cause the rods 191a and 191b to engage the boltassemblies 190a and 190b, respectively. At the same time, the shield isable to move downwardly in response to the weight of the truck body.

The subassembly 61a-c is fitted over the top of the beam 27 such thatthe planar horizontal surface portion 61c provides the supportingsurface for the tubing 47. The horizontal surface is welded to the twowing portions 61a and 61b in order to allow the first portion 61c to fitover the top of beam 27 in much the same manner as a saddle on a horse'sback. The shield 49 and plate 60 are fitted over the tubing 47 in thesame manner as discussed in connection with FIG. 6. In order to providehorizontal stability for the tubing 47 and the shield 49, verticalguides 65a and 65b are integrally attached to opposing ends of theplanar horizontal surface of portion 61c. The guides 65a and 65bcooperate with the side walls of the shield 49 to inhibit anyside-to-side movement of the tubing 47. The dashed line indicated as 27'is included to indicate the beam 27 may be a square beam instead of theI-beam illustrated.

Referring to FIGS. 8, 8a and 9, an end clamp 68 at the end of eachtubing 47 assures that the interface of the tubing 47 and one of thesensors 51a-d remains intact throughout the life of the on-boardweighing device. As illustrated in FIG. 9, a collar 70 retains thetubinng 47 in a cavity formed by joining top and bottom portions 70a and70b, respectively, of the collar 70. End clamp 68 has similar top andbottom portions 68a and b, respectively, and also a center portion 68cas shown in the exploded view in FIG. 8a. The end clamp portion 68cincludes a centrally-tapped hole for receiving a threaded extension ofone of the sensors 51a-d which join to secure and seal the end of thetubing 47. Because of the pressure exerted on the tubings 47 when theysupport the weight of the truck body 13, there is a substantial forceacting at the ends of the tubings. Each end of the tubings 47 must beterminated in a manner which assures the tubing will not rupture. Themetallic collar 70 restrains the end of the tubing 47 where it joinswith the clamp 68 and one of the sensors 51a-d in order to prevent arupture at the tubing-sensor interface provided by the end clamp 68. Tofurther assure the tubing 47 remains sealed at the end clamps 68, verystrong, high quality adhesives of commercial grade are added between thetubing 47 and the end clamp portions 68a,b and c in order to form astrong bond at the clamp-tubing interface. The adhesive is also addedbetween the inner walls of the tubing at its end in order to aid in itssealing. As indicated by FIG. 8, bolts secure the respective upper andlower sections of both the end clamp 68 and the collar 70.

Referring to FIG. 10, in an alternative embodiment of the on-boardweighing device according to the invention, the cushioning supportmaterial 52 remains on the parallel beams 26 and 27 to provide acushioned interface between the truck frame 15 and the truck body 13,but each of the beams 28 and 29 of the truck body 13 is modified so thatthey include the on-board weighing device as described in connectionwith FIGS. 1-4. The two pieces illustrated in FIG. 10, sections 29a and29b of the beam 29, are joined by a plurality of bolts 57 extendingalong the length of the two-piece beam. The two pieces of beam 28 (notshown) are constructed and joined in the same manner. By providing atwo-piece beam construction with tubing 47 or load cells (not shown)sandwiched between the two pieces, the total weight of the truck's loadcan be accurately measured in accordance with the invention, ie.,without lifting the truck body 13 off the truck frame 15.

Although this alternative embodiment requires the modification of thetruck body 13, there is no required modification of the truck frame 15or the cushioning material, and therefore, there is no possibility of astructural weakening of the load's support surface (i.e., the truckframe). Moreover, since the modification of the truck body merely makestwo pieces from what formerly was one piece, there is also little dangerof reducing the structural integrity of the truck body. Specifically,the weight of the load is continuously distributed through the tubings47 along the length of the interface between the two pieces of the truckbody, thereby assuring that there are no high stress areas which mightbe susceptible to fracturing under heavy loads.

In some vehicle manufacturer's truck designs, when the truck body 13 isin its lowered position the weight of the truck body is supported at theback end of the body by way of the hinge assemblies and at the front ofthe body by way of a relatively small body-frame interface area. Whenthe body is in its lowered position, the body area intermediate thesetwo support areas is suspended over the frame as shown in FIG. 12. Forthese types of truck bodies there is no cushioning support materialalong the length of the parallel beams of the frame. When the truck bodyis in its lowered position, the interface area 55 supports the beam 29of the truck body 13 on the beam 27 of the frame 15 at the end of thebody opposite the hinge assemblies 17, thereby preventing the body frombeing cantilevered. For these types of truck constructions, an on-boardweighing device according to the invention is provided by positioningload sensors 57 and 59 at the interface area 55 and at the hingeassemblies 17, respectively, since these are the two points that supportthe truck body over the truck frame 15 when the body is in its loweredposition. A particular example of a load cell suitable for use inconnection with the embodiment of FIG. 10 is the fatigue-resistant loadcell (models 3116 or 3152) manufactured by Lebow Assoc., Inc. of Troy,Mich.

As an alternative to positioning the load cell 59 in FIG. 12 at thehinge assembly 17, the load cell may be located between the interfacebetween beams 27 and 29 (indicated as 59' in FIG. 12) if the hingeassemblies 17 are modified, as needed, to provide a "floating" hinge pinas shown in FIG. 3a. With a floating hinge pin, the weight of the truckbody will be fully supported along the interface between the beams 27and 29 and, thereby, the load cells 57 and 59' will provide an accurateindication of body weight. As a further alternative, a shortened versionof the on-board weighing device of FIGS. 1-9 may replace the load sensor57 while maintaining the load sensor 59.

Referring to FIG. 13a, the off-road, heavy duty truck includes apressure sensor added to the hydraulic line connected to the hydrauliccylinders 19 and 21; by providing a pressure measurement from thehydraulic line of the hydraulic cylinder 21, in addition to the pressuremeasurement provided by the on-board weighing device, a determinationcan be made of the weight distribution of the load over the front andrear axles 71a and 73a, respectively, by summing moments about the hingeassemblies 17. By summing the moments about the hinge assembly 17, thelocation of the center of gravity of the load carried by the truck body13 can be determined. By determining the location of the center ofgravity of the load carried by the truck body 13, the relativedistribution of the total weight of the load over the front and rearaxles can be determined.

In order to determine the axle loads, the truck 11 may be schematicallyrepresented as a horizontal line 74 in FIGS. 13a and 13b which passesthrough both front and rear axles. In practice, the vertical height ofthe load's center of gravity is not important; therefore, the momentequation about the hinge assemblies 17 (the vertical height of the hingeassemblies is also ignored) gives the one dimension of the location ofthe center of gravity of the load which is important in determining theaxle loads, i.e., its location relative to the front and rear axles.

In order to determine the location of the center of gravity of the loadalong the length of the truck 11 as shown in FIGS. 13a and 13b, thetruck body must be lifted slightly from its lowered position as shown bythe distance h in FIG. 13b in order that the hydraulic cylinders 19 and21 provide a pressure reading indicative of the force required to pivotthe truck body 13 about the hinge assemblies 17. By providing thehorizontal line 74 with a calibration in predetermined units such asinches or feet, the horizontal placement of the center of gravityrelative to the front and rear axles can be determined.

Since the hydraulic cylinders 19 and 21 are positioned at an angle Φwith respect to a vertical axis perpendicular to the horizontal line 74in FIGS. 13a and 13b, the pressure reading from the pressure transducerassociated with hydraulic cylinders 19 and 21 must be multiplied bycylinder area (to provide a force measurement) and by the cosine of theangle Φ in order to determine the vertical force at the cylinder hingeassembly 33. Although the angle Φ changes with the extension of thehydraulic cylinders 19 and 21, a predetermined value for the angle Φ canbe stored in the memory of the process associated with the on-boardweighing device as discussed hereinafter since the truck body 13 need beraised only a slight amount (shown as the distance h in FIG. 13b) suchthat the angle Φ can be treated as a constant for purposes ofdetermining the relative axle loads.

Once the vertical force at the cylinder hinge assembly 33 is determined,the equation for the moments about the body hinge assembly 17 and alongthe horizontal axis has only one unknown, i.e., the horizontal distanceof the center of gravity from the body hinge assembly 17. The followingequation expresses the relationship of the moments about the body hingeassembly 17:

    (Total Weight)·(C/G)-(Cylinder Weight)·(cos Φ)·(y+z)=0                                   (1)

wherein "Total Weight" is the most recent pressure reading from theon-board weighing device representing the load carried on the truckframe 15 multiplied by a predetermined constant to provide a forcemeasurement, and C/G is the location of the center of gravity of theload projected onto the horizontal line 74; "Cylinder Weight" is thepressure from the pressure transducer in the hydraulic line to hydrauliccylinders 19 and 21 multiplied by the area of the cylinders; the angle Φis the angle formed by the longitudinal axis 75 of the cylinder 21 and avertical axis 76 in FIGS. 13a and 13b; and (y+z) is the distance on thehorizontal line 74 between the body hinge assembly 17 and the cylinderhinge assembly 33. Solving for the location of the center of gravity,the equation is as follows: ##EQU1##

With the horizontal position of the center of gravity located, the loadon each axle can be determined by solving for the axle weights using thesum of the moment arms about the axle and along the horizontal line 74.For the front axle, the sum of the moment arms about the rear axleprovides an equation for solving for the load on the front axle. Theequation for the moment arms about the rear axle is as follows:

    (Weight on Front Axle)·(w)-(Total Weight)·(C/G-z)=0 (3)

Solving for the weight on the front axle, the equation becomes, ##EQU2##

To find the load on the rear axle, the moment arms are taken about thefront axle as set forth in the following equation: ##EQU3## The weightof the frame of the truck 11 bearing on the front and rear axles (i.e.,the tare weight) can be added to the calculated weights in order toprovide total weights bearing on the front and rear axles. To find thetare weights for the front and rear axles, the truck 11 may simply beweighed one axle at a time on a platform scale as in FIGS. 15a-b. Inmeasuring this tare weight, the truck body 13 may be removed from thetruck 11 or the weight of the body attributable to the front and rearaxles may be subtracted from the weight recorded by the platform scale(FIGS. 15a-b). The resulting weight measurement may be stored in thememory of the electrical circuitry associated with the on-board weighingdevice as discussed hereinafter.

Since the horizontal distances represented by the values for w, x, y andz are known and since the pressure in hydraulic cylinders 19 and 21 isknown when the truck body 13 is lifted slightly off the frame 15, thecenter of gravity for the load (weighed by the on-board weighing device)can be determined from equation two. Once the center of gravity for theload is determined, the distribution of the load between the front andrear axles, 71a and 73a respectively, can be easily determined fromequations four and six.

Determination of axle loads can be made in off-road vehicles of othertypes using a similar approach as disclosed in connection with theoff-road truck of FIGS. 13a-b. For example, a scraper vehicle 81, shownin its raised and lowered positions in FIGS. 14a and 14b, respectively,utilizes a pressure sensor in connection with its hoist cylinder 82 toestimate the front and rear axle loads of the scraper. A scraper vehicleloads ground material into its body by lowering an open end of the bodyinto contact with the ground. As the scraper moves forward, the groundmaterial is swept into the body of the scraper by way of the loweredopening. In other words, the bottom edge of the body scrapes the groundsurface, hence the name "scraper".

The mechanism which lifts and lowers the body 83 of the scraper 81 aremost clearly shown in FIGS. 14c-d. In its lifted or raised position, thehoist cylinders 82 (only one is shown) holds the body 83 off the ground.In order to prevent material from falling out of the body 83, a gateassembly 84 is provided to close the opening in the body 83 when it isin its lifted or raised position. Control of the gate assembly isprovided by a linkage 85 in a well-known manner.

Referring back to FIG. 14a, longitudinal dimensions v, w, x, y and z ofthe scraper 81 are used to calculate an approximate axle load for thefront and rear axles 86 and 87, respectively. In the same manner as usedin connection with the axle load determination for an off-road truck,the moment arms about the front and rear axles serve as the tools todetermine the axle loads. Unlike the off-road truck, the center ofgravity for the load in the body 83 of the scraper 81 cannot be aseasily determined. In the off-road truck of FIGS. 13a-b, the on-boardweighing device combined with a pressure sensor in the hoist cylindersystem to find the center of gravity for the load. In the scraper 81,the center of gravity for the load of the scraper body 83 must beapproximated. For illustration, the scraper 81 in FIG. 14a is assumed tohave a center of gravity at the pivot point 88 of the pivot arm 89. Withthe location of the center of gravity assumed, the total weight of theload can be determined and, as a result, the forces on the axles canalso be determined.

To calculate the axle loads, the weight of the load must first bedetermined. Converting the pressure in the hoist cylinder 82, while thebody 83 is in a raised position, to a force allows the moment arm aboutthe front axle to be solved for the weight of the body 83. Since thehoist cylinder 82 is at a slight angle Φ from vertical, the force F₂must be multiplied by cos Φ to find the vertical force for calculatingthe moment arm about the front axle. The equation is as follows:##EQU4## where F₁ is the weight of the body 83 and F₂ is the force atthe hoist cylinder 82 lifting the body.

Once the weight of the load is determined, the axle loads are easilycalculated as follows: ##EQU5## where F₄ is the weight on the rear axle87, and ##EQU6## where F₃ is the weight on the front axle 86. Theforegoing calculation may be implemented by the circuitry and flowchartsdiscussed in connection with FIGS. 16, 17 and 18a-r. Although theflowchart discloses steps for calculating the axle loads for a dump bodytruck using data gathered by the on-board weighing device and data fromhoist cyclinders, it will appreciated from the foregoing scraperdiscussion that similar software steps may be used in connection withthe circuitry of FIGS. 16 and 17 to calculate scraper body weight andaxle loads.

As briefly mentioned earlier, the platform scale of FIGS. 15a-b may beused to measure the tare weight for the front and rear axles of theoff-road truck of FIG. 13a-b or the scraper of FIG. 14a-d. The tareweight is stored as a "hard number" in an electronic memory and added tothe calculated axle weights from the load in order to arrive at thetotal axle loads. An exemplary platform scale may be implemented byappropriate changes to the on-board weighing device. Specifically,referring briefly to FIGS. 15a and 15b, an inexpensive platform scale isillustrated using tubing, sensors and support structure similar to thatused for the on-board weighing device. A plurality of tubing lengths 90are positioned under a surface plate 91. In order to hold the surfaceplate 91 in a stable position to prevent sliding, two rows of pins 92integral with the plate are received in a corresponding two rows ofsockets 93 integral with a bottom plate 94. Sensors (not shown) areattached to one end of each tubing 90 or, if the tubing is crimped atits center, the sensors may be attached to each end of the tubings.

A contact plate 95 interfaces the tubings 90 to the surface plate 91.The contact plate maintains a constant area of contact between thesurface plate 91 and the tubings 90. In order to prevent the tubingsfrom wandering on the bottom plate 94, each tubing 90 is bordered alongits length with projections 96 from the bottom plate 94. In operation,the platform scale is recessed into the ground in order that the surfaceplate 91 is flush with the ground. In order to weigh, for example, thefront or rear axles of the truck in FIGS. 13a and 13b, the truckoperator merely drives the truck over the platform such that all frontor rear tires bear on the surface plate. The pressure increases in thetubings 90 is sensed by the pressure sensors and circuitry similar tothat illustrated in FIG. 16 adds the individual pressure readings andconverts the sum to a weight measurement.

Referring now to FIG. 16, the electrical circuitry which completes theweighing system by manipulating the pressure data received from theon-board weighing device is provided by a sensor processing unit 101(previously referred to as the "processor means"). Preferably, the unitis microprocessor based. As will be apparent to those skilled in theart, the sensor processing unit 101 includes a central processing unit103 (hereinafter CPU 103), an associated program memory in the form of aPROM 105 and read/write memory RAM 107. A first memory portion of theRAM 107 functions as a first storage array for pressure readings fromthe on-board weighing device (hereinafter referred to as an ARRAY I).ARRAYS II and III are for summaries and archives, respectively. Thestorage arrays will be discussed in greater detail in connection withFIG. 16a. A particular example of a CPU suitable for the sensorprocessing unit 101 is the Z80 microprocessor manufactured by IntelCorporation of Santa Clara, Calif. Another possible microprocessor isthe 8085 from Intel.

In conventional fashion, emanating from the CPU 103 is a microcomputerbus 109. The bus 109 is connected to the memories 105 and 107 as well asto input ports 113 and 115. The microcomputer bus 109 communicates to avisual display unit 117 and a printer 119 by way of a display drive 120and a printer drive 121, respectively. In order to provide the sensorprocessing unit 101 with the operator and truck member, themicrocomputer bus 109 is connected to a keyboard 122 by way of aninterface 124. The keyboard 122 also provides the sensor processing unit101 with a conversion factor for converting the stored pressure readingsto weight values in tons, pounds or kilograms. Also, communicating tothe sensor processing unit 101 by way of the microcomputer bus 109 is atime clock 126. In order to provide a communications path between thesensor processing unit 101 and the printer 119, the visual display 117,the time clock 126 and the keyboard 122, the microcomputer bus 109includes data lines, memory lines and control lines.

In order to measure the axle loads of the truck 11, an interruptinstruction instructs to the sensor processing unit 101 to execute thesoftware routine for calculating the axle loads from pressure readingsof the on-board weighing device and the pressure sensor 139. Asillustrated in FIG. 16, the interrupt signal is activated by the truckoperator by way of a push button 142. As mentioned in connection withFIG. 13, the interrupt is activated only after the operator has slightlyraised the truck body 13 by extending the hydraulic cylinders 19 and 21.

As previously mentioned, hauling parameters derived from the on-boardweighing device and processed by the sensor processing unit 101 can beidentified with particular I.D. numbers, thereby providing an indicationof truck and operator performance. It will be appreciated by thoseskilled in the art that keyboard 122 can also serve as an I.D. input formechanics, oilers and other maintenance personnel in order to record themaintenance work on the truck (in a fifth array of RAM 107) and theidentity of the individual who performed the maintenance. In connectionwith recording a user's identification number, the sensor processingunit 101 controls an ignition lock-out device 127 which allows the truck11 to be started only if a correct I.D. number has been received. Inorder for the sensor processing unit 101 to detect changes in operatornumbers when the truck is not running (for instance, a change from amechanic's I.D. to an oiler's I.D.), power is continuously applied tothe sensor processing unit. In a well-known manner, the sensorprocessing unit 101 reverts to a stand-by mode when the truck is turnedoff in order to reduce its power consumption and thereby prevent aserious drain on battery power. In the stand-by mode, the sensorprocessing unit periodically powers up and looks to see if activity hasoccurred at its sensor inputs. If, for example, a new I.D. number hasbeen entered into thekeypad 122, the unit stores the new number andprints and/or displays a summary of data while the truck 11 was undercontrol of the previous number. (The foregoing display of summary datawill be explained in greater detail in connection with FIG. 18i). As analternative to entering the I.D. number by way of the keyboard 122, anencoded card may be used by the operator in connection with a cardreader.

As will be explained in greater detail in connection with the flowchartof FIGS. 18a-f, h-k, m, p and r, the sensor processing unit 101 and itsassociated electronics are energized in response to engine start-up. Anengine start-up energizes the CPU 103 which in turn initializes theprogram memory, thereby beginning the program routine of the flowchartin FIGS. 18a-f, h-k, m, p and r.

Each of the various alternative embodiments of the on-board weighingdevice provide the circuitry of FIG. 16 with an analog electrical signalwhich is linearly proportional to the pressure exerted by the tubingfluid on the device's sensors 51a-d (tubing in the preferred embodimentof the invention or load cells, strain gauges or like pressure sensingtransducers in alternative embodiments of the invention). Since thepressure of the tubing fluid is linearly proportional to the weight ofthe truck body 13 and since the sensors 51a-d reflect the tubing fluidpressure in a linear fashion, the analog signals from the sensors areproportional to the weight of the truck body.

Sensors 135, 137, 138 and 139 cooperate with the on-board weighingdevice in order to provide information necessary for the sensorprocessing unit 101 to provide output information to the truck operatorsuch as the loads on the front and rear axles as discussed in connectionwith FIGS. 13a and 13b. The gear sensor 135 is used in connection with arecord keeping function performed by the software of the sensorprocessing unit 101 such that, in response to a gearshift by the truckoperator, certain information stored in RAM 107, and derived from theon-board weighing device, may be manipulated (as explained more fully inconnection with the flowcharts of FIGS. 18a-f, h-k, m, p and r). In asimilar manner, the dump sensor 137 is utilized by the sensor processingunit 101 to manipulate stored data from the on-board weighing devicewhen the dump sensor 137 indicates that the truck body 13 has beenpivoted to its dump position. Preferably, the dump sensor is a mercuryswitch mounted to the truck body 13 in order that it may respond to thechange in the body's position as a load is dumped. Unlike mechanicalswitches, which are used in all prior apparatus, to the best ofapplicant's knowledge, a mercury switch when utilized as a dump switchoffers the highly advantageous characteristic of being isolated from theambient conditions. Therefore, the harsh conditions often encountered byoff-road vehicles will not cause a rapid deterioration of switchperformance.

The distance sensor 138 is used by the sensor processing unit 101 toprovide the distance measurement in connection with the calculation oftons-miles per hour units used to indicate the degree of tire wear oruse. Finally, the pressure sensor 139 is located in the hydraulic lineof the hydraulic cylinders 19 and 21 and provides a pressure measurementfor use in connection with calculating the axle distribution of thetotal load. The interaction between the sensor processing unit 101, theon-board weighing device and each of these sensors is discussed ingreater detail hereinafter in connection with the flowcharts of FIGS.18a-f, h-k, m, p and r which disclose the program routine for the sensorprocessing unit. All of the foregoing sensors are analog devices whichrequire analog-to-digital conversion as represented by A/D block 130. Aswith A/D converter 129, the circuitry comprising these converters isconventional and, therefore, will not be discussed in detail.

In order to provide a visual indication of the unused weight capacity ofthe truck body, the sensor processing unit 101 is connected to a loadindicator 140 by way of the microcomputer bus 109. The load indicator140 includes a plurality of lights 140a-e stacked one above the other.By activating a particular light on the indicator 140, the sensorprocessing unit 101 is able to signal the operator of the loader theproportion of a bucket load which may safely be added to the truckwithout exceeding the weight capacity of the truck. From a predeterminedmaximum weight capacity for the truck stored in the sensor processingunit 101, the sensor processing unit determines the remaining loadcapacity of the truck body 13 from the current load as measured by theon-board weighing device.

If the truck is loaded by a continuous flow of material, instead of theincremental increase provided by the bucket of a front end loader, theindicator 140 may provide a real time indication of the percentage ofremaining load capacity. For example, if a conveyor belt or hopper (notshown) are used to load the truck 11, the sensor processing unit cancompare current load data with a maximum load and activate anappropriate light 140a-e depending on the fraction of remainingcapacity. In this example, it is contemplated the indicator light 140acorresponds to a remaining capacity of 20%, indicator light 140bcorresponds to a remaining capacity of 15%, etc. The sequencing of thelights 140a-e as the truck approaches full load will aid in theanticipation of when the continuous flow should be cut off in order toavoid overflow, yet assure a maximum load. The particular programmingsteps for providing a real time indication of remaining capacity is notset forth in the steps of the flowcharts in FIGS. 18a-f, h-k, m, p andr, but the modifications required to the program for continuous flowloading will be evident to a programmer from the flowchart descriptionof steps responsive to incremental loading.

In connection with the indication of the remaining weight capacity ofthe truck, the sensor processing unit 101 determines the averageincremental increase in the weight of the truck body 13 with each bucketfrom a loader, thereby indicating the average weight of a bucket loadused to load the truck body. If the average weight for a bucket is lessthan the remaining weight capacity of the truck body 13, then the greenlight 140a of the indicator 140 will be activated by the sensorprocessing unit 101. If the average weight of a bucket is greater thanthe remaining load capacity of the truck body 13, the sensor processingunit 101 determines what fraction of the average weight of a bucket theremaining weight capacity most closely approximates.

Specifically, a three-quarter light 140b is activated if the remainingweight capacity of the truck body 13 has a value between three-quartersof an average weight for a bucket and the total average weight for abucket. In order to light the one-half light 140c, the remaining weightcapacity of the truck body 13 must be between one-half andthree-quarters of the average weight of a bucket. Similarly, in order tolight the one-quarter light 140d the remaining weight capacity must bebetween one-quarter and one-half of the average weight of a bucket.Finally, for the red light 140e to be activated and thereby indicate thetruck body 13 is full, the remaining weight capacity of the truck body13 (as determined by the pressure reading from the on-board weighingdevice) must be less than one-quarter of the average weight of a bucket.The manipulation of the indicator 140 by the sensor processing unit 101in response to pressure readings from the on-board weighing device willbe explained in greater detail in connection with the program routine ofthe sensor processing unit illustrated by the flowcharts in FIGS. 18a-f,h-k, m, p and r.

A transceiver 150 is mounted to the truck 11 in an appropriate andconvenient location in order to enable the sensor processing unit 101 tocommunicate with a central computer. As will be explained in greaterdetail hereinafter, the central computer serves as a traffic cop tocontrol the flow of trucks between load and dump sites.

Turning now to the calibration and programmed operation of the on-boardweighing device and the sensor processing unit 101, initialization ofthe system will be explained with reference to the preferred embodimentof the invention. In connection with the alternative embodiments of theon-board weighing device, the modifications required to calibrate thesensor processing unit 101 and the modifications required to the programmemory will be obvious to those skilled in the art from the followingdetailed description of the calibration of the on-board weighing deviceand programmed operation of the sensor processing unit for the preferredembodiment of the invention.

The calibration of the on-board weighing device may be illustrated byconsidering the case of a truck body 13 having a ten-ton empty weightand a 50-ton load capacity. In the preferred embodiment of the on-boardweighing device, if the tubings 47 have a total combined effectivesurface area of 500 sq. in., the pressure developed by the empty truckbody 13 is 40 psi. A fully loaded truck body 13 (i.e., 50 tons) developsa pressure of 240 psi. By utilizing the pressure sensors 51a-d inconnection with the tubings 47, an analog voltage output may be obtainedwhich accurately measures pressures between 0 and 300 psi. The analogvoltage output of the sensors 51a-d varies between two and six volts.For the truck body 13 having an empty weight of ten tons and a full loadweight of 50 tons, the analog voltage from the sensors 51a-d is 2.53volts for the weight of the empty truck body and 5.20 volts for the fullload weight. Therefore, the the voltage outputs of the sensors have avoltage range of 2.67 from no load to full load volts.

At the analog-to-digital converter 129 (hereinafter referred to as anA/D converter) the output voltage from each of the pressure sensors51a-d is converted from an analog voltage to a digital signal. Theoutput from the A/D converter 129 is a binary-coded decimal numberwhich--since it is proportional to the analog voltage from the pressuresensors 51a through 51d--is also proportional to the pressure on thetubings 47. Since the voltage output range of the pressure sensors 51a-dis between two and six volts, the A/D converter 129 converts two voltsto a binary-coded decimal number close to zero (when the truck body islifted off the sensors thereby creating a zero load condition) andcorrespondingly converts six volts to a binary-coded decimal number ofapproximately 255.

For the exemplary truck 11 having a ten-ton empty weight for the truckbody 13, the foregoing calibration procedure provides, at thebinary-coded decimal output of the A/D converter 129, a decimal numberof 34 when the truck body is in its lowered position. In comparison tothe decimal number of 34 which represents an empty load, for a full loadof 50 tons the output of the A/D converter 129 is a binary-coded decimalnumber of 204. Therefore, a decimal range of 170 represents all truckbody loads from empty to full. Therefore, with a pressure range of 200psi (corresponding to a weight range from no load to full load) a rangeof 170 in the binary-coded decimal number from the A/D converter 129gives a resolution of approximately 1.18 psi per decimal number.

In order to calibrate the on-board weighing device for measurement in anappropriate unit of weight (i.e., tons, pounds of kilograms), aconversion factor, which corrects for the contact area between the plate60 (FIG. 6) and the desired units of weight, is manually set into thekeyboard 122 in FIG. 16 and converted to a binary-coded decimal numberby conventional circuitry associated with the keyboard. Thisbinary-coded decimal number is delivered to the CPU 103 by way of theinterface 124. At the CPU 103, the conversion value is multiplied with abinary-coded decimal number representing the previously calculated netpressure for the truck body. The resulting binary-coded decimal productrepresents the numerical value of the net weight of the truck body intons, pounds of kilograms, depending on the conversion factor chosen.For example, the net pressure calculated from the pressure sensors 51a-dfor a full load condition corresponds to a binary-coded decimal numberof 170. The CPU 103 multiplies the binary-coded value of 170 by thebinary-coded decimal number from the keyboard 122.

In order to obtain an accurate measurement of the pressure on the fourisolated lengths of the tubings 47, the sensor processing unit 101 readsthe voltage 16 times in succession from each pressure sensor 51a-d. Inorder to obtain one pressure value for each sensor 51a-d, the 16readings are averaged. Each pressure sensor 51a-d is read and averagedbefore the next sensor is read and averaged. When all of the pressuresensors 51a-d have been read and their 16 separate readings averaged,the four average readings are themselves averaged to obtain one pressuremeasurement for the truck body 13. Since the net weight of the truckbody 13 is the weight of interest, the tare pressure (stored in memoryas a predetermined pressure) is subtracted from the average pressurereading of the pressure sensors 51a-d to obtain a net pressure reading.The net pressure reading corresponds to the weight of the load carriedby the truck 11 in its truck body 13. This reading is stored in ARRAY Iand is manipulated in accordance with the program memory for the CPU 103contained in the PROM 105.

In order to convert the foregoing pressure readings to a weight reading,the effective area of contact between the tubing 47 and the plate 60(see FIG. 7) must be multiplied. The pressure data from the sensors51a-d represents weight per unit area. Multiplying the effective contactarea by the pressure data results in data indicative of weight. Twomethods may be used to find the weight--(1) the average pressure may bemultiplied by the total effective area for all the plates 60 of theon-board weighing device or (2) add the separate pressures from each ofthe sensors 51a-d and multiply the sum by the effective area of only oneof the plates 60. From empirical study, applicant has discovered thatthe surface area of the plate 60 is not the precise area used tomultiply with the pressures. A slightly modified, enlarged surface areais required in the calculation of weight. The degree of enlargment isdetermined empirically. Of course, the pressure x area product may alsorequire conversion to provide the appropriate weight units, e.g.,pounds, kilograms, etc.

For the foregoing calculation of weight, the effective area of contactbetween the tubing 47 and the plate 60 is considered to be the same foreach sensor 51a-d. If the specific system design results in unequalareas, each pressure and area must be treated separately. Therefore, ifthe four lengths of tubings 47 in FIGS. 1-4 include two short forewardsections and two long aft sections, the two forward sections must betreated separately from the aft sections in order to provide ameaningful single weight calculation.

In order to record the relevant data provided by the on-board weighingdevice and the electronic circuitry of FIG. 16, the RAM 107 is organizedto not only include the miscellaneous temporary storage (e.g., statusflags) required for normal software operation, but the RAM also includesarrays of data cells for storing time and pressure data to provide achronologicl record of truck and operator performance and to provide adata base to extract further data indicative of performance. Referringto FIG. 16a, the RAM 107 is schematically illustrated as including atleast a miscellaneous storage area and seven arrays.

ARRAY I provides storage locations for a plurality of consecutive netpressure values calculated from the pressure sensors 51a-d of theon-board weighing device. Also in RAM 107, storage locations areprovided for cataloging summaries of hauling parameters wherein thesummaries are indexed by operator number in order that the performanceof each operator of the truck 11 can be quantified. For example, ARRAYSII and III are provided in RAM 107 wherein the ARRAY II collectssummaries of hauling parameters for a time duration measured from thetime a particular operator number is entered into the system until thenumber is changed. Entry of a particular operator number may identify acertain cell in the second array for receiving summaries of haulingparameters, thereby identifying the summaries with the operator. Byproviding a non-volatile memory for the RAM 107, an ARRAY III serves asan archive for the summaries in ARRAY II, thereby providing a record ofoperator performance for a period of time including multiple uses by theoperator, e.g., a month, quarter or year.

A fourth array, ARRAY IV, provides a storage area for recordingmaintenance work on the truck. Entry of a user I.D. number indicative ofmaintenance personnel rather than drivers are stored in ARRAY IVtogether with relevant data such as time under control of themaintenance number. Two additional arrays, ARRAYs V and VI store dateuseful in evaluating the performance of an off-road, heavy duty truckand its loader. As will be discussed in greater detail hereinafter,ARRAYs V and VI store data relating to the weight of each bucket addedby the loader and the real time of each bucket addition. The purpose andmanipulation of these stored values in ARRAYs I-VI will be discussed inconnection with the flowchart of FIGS. 18a-f, h-k, m, p and r.

Finally, ARRAY VII is an area for storage data to be downloaded from theon-board system to a remote central location for creating a historicalfile. As will be apparent from the discussion in connection with theflowcharts of FIGS. 18a-f, h-k, m, p and r and 20a-b, relevant data canbe either or both displayed on-board and downloaded to a centralcomputer. If downloading is a selected option, the data is temporarilystored in ARRAY VII for transmission in response to receiving anappropriate control signal from the central computer.

In a simpler, less costly device, the circuitry of FIG. 16 may bereplaced by a mechanical weight indicator 169 such as the one shown inFIGS. 17a-c. The sensors 51a-d are removed from the tubings 47 and theoil is continuous from each of the tubings to one of the piston chambers170a-d. Within each chamber 170a-d is a piston 171a-d as exemplified bythe piston in FIG. 17c, shown in perspective. Each piston 171a-d is diskshaped and seals the chambers 170a-d into top and bottom volumes withthe aid of O-rings 172a-d.

Since the weight of the truck body 13 is proportional to the sum of thepressures from the plurality of tubings 47 of the on-board weighingdevice, the mechanical weight indicator 169 adds the separate pressuresand displays the total pressure by way of a conventional pressure gauge175. Once the system is calibrated, the pressure gauge 175 may besupplemented with a weight scale such that weight can be read directlyfrom the gauge. It will be appreciated from the following descriptionthat addition pistons 171 and piston chambers 170 may be easily added tothe indicator 169 if more pressure inputs are required.

Referring to FIG. 17b, a plurality of pistion chambers 170a-d arestacked one above the other and, they include pistons connected bylongitudinal shafts 176b-d as shown. Each of the shafts 176b-dcommunicate the force from the piston below it to its piston.Correspondingly, this latter piston adds the force on it from theprevious piston to the force from the oil pressure and passes the sum tothe next piston above it by way of its shaft 176, etc. The last pistonhas the sum of all the forces from the pressures on the other pistonsbelow it. Since the lowermost piston 171a does not have a piston belowit, it does not require a shaft 176.

In order for the full force of one piston to be transferred to the nextpiston, the top volume of each piston (except for the last or uppermostpiston) is vented to the atmosphere through vents 177a-c. Of course, theoil intake ports 178a-d are located in the bottom volume of each chamber170a-d. In order to separate the bottom oil-filled volume from anadjacent top, air-vented volume, chambers 170a-c include disk sections179a-c, respectively. These sections include central bores 180a-c,respectively, for receiving the shafts 176b, c and d. Each central boreis sealed by a gasket. An annular grove 181 in the ends of each of thechambers 170a-d receives O-rings in order to provide a sealed indicator169. Each of the disk sections 179a-c include annular recesses on theirtop and bottom surfaces for receiving the cylindrical chambers 170a-d.

In its assembled state, the mechanical weight indicator 169 is capped bytop and bottom plates 182 and 183, respectively. A plurality of rods 184in FIG. 17a extend the length of the indicator 169 and join the top andbottom plates 182 and 183. Threaded ends of the rods 184 receive nutsfor securing the entire assembly.

In order to equalize pressure between input lines during set up of theindicator 169, valves 185a-c interconnect the input lines from theon-board weighing device. During set-up, the valves 185a-c are openedand the fluid pressure is allowed to equalize. The valves 185a-c arethen turned off and, they remain off during normal operation. In each ofthe lines from the tubings 47 is a flow restrictor 186 for protectingagainst sudden changes in pressure (i.e., spikes) from reaching thegauge 175. Also on each input line is a air column 187 for protectingthe on-board weighing device from possibly drawing a vacuum in the eventof a significantly uneven distribution of weight. The top chamber 170dis filled with fluid in both its top and bottom volumes in order thatthe added pressure can be passed to the pressure gauge 175 by way of thetop volume and the output port 189.

In a simple system, the mechanical weight indicator may be located offthe truck and at a stationary site. For example, where the loadingequipment is stationary during loading, a coupling between the on-boardweighing device and the stationary mechanical weight indicator may allowthe operator of the loader to remotely monitor the weight of the vehicleload without the need for relatively expensive transceivers. Obviously,in such a system, the sensors 51a-d are absent and the coupling betweenthe on-board weighing device and the mechanical weight indicator issimply a conduit for communicating the pressurized fluid from the truckto the statinary location.

In order to allow the loaded vehicle to move away from the loading site,the coupling between the on-board weighing device and the mechanicalweight indicator 169 includes a quick disconnect device of conventionaldesign. In operation, the vehicle is moved into position for loading andthe male and female members of the quick disconnect device are joined soas to allow pressure from the on-board weighing device to be directlytransferred to the stationary mechanical weight indicator 169. Since theloading equipment is stationary, the indicator 169 is preferably mounteddirectly to the loader so that the loader operator can monitor theincreasing weight of the load. When a full load is indicated, the quickdisconnect device decouples the mechanical weight indicator 169 and theon-board weighing device so that the truck may move away from theloading site and allow a new truck to be positioned for loading. The newtruck is coupled to the mechanical weight indicator 169 as before andthe foregoing steps are repeated. An obvious variation to the foregoinghydraulic system would be the upgrading of the system to an electricalsystem wherein the sensor 51a-d are present on the on-board weighingdevice and a transmitter porivides the means to communicate the pressuredata to an electronic weight indicator located at the loader. Of course,a simplified version of the sensor processing unit 101 is necessary inorder to prepare the pressure data for transmission. The stationaryweight indicator may be merely a receiver of the data which converts thetransmitted pressure data to a weight display for the operator of theloader.

Referring now to the flowchart of FIGS. 18a-18r, the main program of thesensor processing unit 101 for executing all aspects of the invention isillustrated by the flowchart in FIGS. 18a-18e. Various subroutines arecalled from the main program for executing particular aspects of theinvention. These subroutines are illustrated by the flowcharts in FIGS.18f, h-k, m, p and r. Although these flowcharts are intended to becomplete for an operating system, it will be understood that obviousmodifications may be made to the program if a user wishes to use lessthan all aspects of the invention or, in the extreme, simply wishes totransmit pressure data to a remote site as briefly discussed inconnection with FIGS. 17a-c.

For the purpose of reducing the complexity of the flowcharts, themultiple steps required to calculate a single pressure value for thepressure sensors 51a-d as described above are treated in the steps ofthe flowchart as a single step. It will be understood, therefore, thateach step requiring the sensor processing unit 101 to read the pressureof the truck body requires the voltage signal from each of the sensors51a-d to be read in accordance with the following protocol: (1) readingeach sensor 16 times in succession, (2) averaging the 16 readings, and(3) averaging the averaged readings from all the sensors in order toobtain a single averaged reading.

Upon starting the truck, the sensor processing unit 101 receives powerand starts the processing steps of the flowcharts. It begins byinitializing required values at step 210. From step 210, the sensorprocessing unit 101 moves to step 230 where it reads the time and datefrom the time clock 126 of the CPU. Next, as indicated by step 240, thedate, truck identification number, time and operator identificationnumber are printed by printer 119 or transferred to ARRAY VII for latertransmission via transceiver 150. (The truck I.D. number has beenpreviously placed in permanent memory.) As will become more apparent inconnection with the remaining explanation of the flowchart steps,virtually all data identified for an output may be transferred to ARRAYVII in order to download the data to a remote location. Radio linkdownloading will be discussed in greater detail in connection with FIGS.19a-c and FIGS. 20a-b. The operator identification number is obtainedfrom the keyboard 122 as indicated by step 250. At step 260, a count ispreset to a maximum count in order to control later sequencing of thesoftware as explained more fully hereinafter.

After the truck has been turned on and the sensor processing unit 101initialized in steps 210 through 260, the program moves to the mainprogram loop at step 269 where the distance recorded by the distancesensor 138 is added to a previously calculated total distance in orderto update the total distance traveled by the truck. From step 269, theprogram calls a Read Pressure Subroutine (FIG. 18h) at step 270 whereinthe unit reads the pressure from the pressure sensors 51a-d andcalculates an average pressure in the manner previously described. Inaddition, the subroutine also calculates a fore, aft and side-to-sidepressure for use in connection with other subroutines as explainedhereinafter.

In step 275, the program compares the stored operator number with thecurrent operator number entered into the keyboard 122. If the number isdifferent, the new operator number is stored and the program calls theOperator Summary Subroutine at step 277 for analyzing hauling parametersmeasured during operation of the truck 11 while under the control of theprevious operator. The Operator Summary Subroutine is discussed ingreater detail in connection with FIG. 18i. After the Operator SummarySubroutine has been executed or if a change in operator number did notoccur in step 275, the program moves to step 280.

In step 280, the predetermined value for the tare pressure is subtractedfrom the average pressure calculated in step 270 in order to obtain anet pressure value. Since the tare pressure represents the weight of theempty truck body, the net pressure represents the weight of the loadcarried in the truck body 13. From step 280, the sensor processing unit101 moves to step 285 (FIG. 18b) where it is determined if the netpressure value is less than zero. If the net pressure is found to beless than zero in step 285, the program branches to step 286. In step286, the program zeros the net pressure and bucket pressure (bucketpressure will be explained hereinafter in connection with the LoadAnalysis Subroutine, FIG. 18k). At step 289, the net pressure is storedin the first location of ARRAY I, i.e., ARRAY I(1). The most recent 16net pressure values are stored in ARRAY I. These 16 values are averagedin step 300 (FIG. 18b) in order to obtain a time averaged net pressure.

In step 304, the program checks to determine if the operator hasactivated the push button 142 (FIG. 16) to indicate that the axle loadsshould be calculated. If the push button is pressed, the programbranches the main program and executes the Axle Load Analysis Subroutinein step 305. As will be explained in greater detail in connection withFIG. 18p, the Axle Load Analysis Subroutine utilizes the net pressurereading for the truck body and the net pressure from the pressure sensor139 (FIG. 16) to determine the loads on the front and rear axles.

Referring to FIG. 18c at step 380, the sensor processing unit 101determines whether a gear shift has been sensed by the gear sensor 135.If it has, the program branches to step 390. In step 390, the sensorprocessing unit 101 commands the printer 119 to print (or to store inARRAY VII) (1) the gear from which the truck has shifted, (2) the mostrecently calculated average net weight, (3) the time spent in theprevious gear and (4) the distance traveled in the previous gear(derived from the distance sensor 138 in FIG. 16). Although not shown inFIG. 18c, a flag may be set in step 390 indicating a gear shift for usein connection with downloading data to a central computer discussed inconnection with FIGS. 19 and 20. If the truck's gears have not beenshifted in step 380 or after completion of the printing function by theprinter 119 in step 390, the sensor processing unit 101 determines atstep 395 whether the time clock 126 is to be corrected (e.g., change toor from daylight savings time).

If the time is to be corrected, the program branches to step 396 wherethe time correction is executed. From steps 395 or 396, the programmoves to step 400 and determines whether the dump sensor 137 has beenactivated. If the dump sensor has not been activated at step 400, theprogram branches to step 405 to decide if 0.1 seconds have elapsed sinceleaving step 304 and entering step 405. Since step 405 returns theprogram to step 380 if 0.1 seconds has not elapsed, the delay gives thesensor processing unit 101 an adequate time window for sensing theactivation of the dump sensor 137 at step 400 before proceeding furtherin its program. If 0.1 seconds has elapsed in step 405, the programbranches back to step 269 (FIG. 18a).

If the dump sensor 137 is determined to be activated in step 400, theprogram moves to step 406 wherein a Dump Subroutine is called whichsummarizes pertinent data of the haul cycle. In addition to identifying,calculating and printing different parameters for a single hauling cyclein the Dump Subroutine, it will be appreciated that the data gathered bythe sensor processing unit 101 from the on-board weighing device and theassociated sensors may be stored in ARRAY II for a number of haulingcycles in order to provide daily totals or averages of an operator suchas, for example, the total tonnage hauled per day, the number of loadshauled per day, the average load hauled on a particular day and theaverage elapsed time for a haul cycle. The Dump Subroutine is more fullyexplained in connection with FIG. 18r. From step 406, the programcalculates the net pressure in step 410. As indicated in step 410, theresulting single pressure value is stored in the RAM 107 at a locationdesignated for storage of a body-up pressure reading (i.e., a pressurereading corresponding to the truck body raised off the on-board weighingdevice).

In order to provide an indication for other parts of the program that adump has occurred, a dump flag is set in step 420. This signal, with agear change signal and a load signal (discussed in connection with FIGS.18k and m), provide sufficient information to a central computer for itto control the distribution of trucks 11 to the loader 160 in a mannerto minimize load cycle time. This aspect of the invention will bediscussed in greater detail in connection with FIGS. 19a-b and FIGS.20a-b.

In steps 430 and 435, a calculation is performed to update the recordedamount of tire use. In step 430, the distance traveled since the lastcalculation (the last calculation was taken when the truck began loadingas will be explained in connection with the Load Analysis Subroutine ofFIGS. 18k and m) is multiplied with the total truck weight, i.e., themeasured body weight plus the tare weight of the truck. In step 435, the"ton.mile" data from step 430 is summed with prior "ton.mile" data. Thetotal ton.mile data provides an indication whether the tires of thetruck 11 are wearing in accordance with their ton.mile rating. This datacan be very important to a mine operator since reliable data regardingtire wear is otherwise unavailable and since replacement of worn tiresis expensive. A calculation for ton.mile is executed by the sensorprocessing unit every "segment" of a load cycle for which there is achange in body weight; that is, at the end of a haul after the truck hastraveled from loader to dump site and at the beginning of a haul afterthe truck has traveled from the dump site to a loader. The time for thecurrent segment of the load cycle is stored in step 440. The elapsedtime indicates how long it took for this load to be delivered to itsdestination, i.e., from last dump to present dump.

By printing in step 450 (or storing in ARRAY VII for later transmission)the current average net weight (calculated in the subroutine of FIG.18f) in response to activation of the dump sensor 137, the sensorprocessing unit 101 provides a hard copy of the truck's load immediatelybefore the load is dumped by the pivoting of the body about hingeassemblies 17. The elapsed time for this load cycle is also printed. Thecurrent time is read in step 455. Finally, if it is determined at step460 that the current time is greater than the last full hour of the timelast read in step 460 plus one, the CPU 103 commands the printer 119 torecord the time of the dump in step 470. In order to initialize step 460for its next execution, step 475 sets the present whole hour equal tothe previous hour.

Referring to FIG. 18d, in order to re-initialize the sensor processingunit 101 after a load has been dumped, the net pressure array, i.e.,ARRAY I, is filled at all of its 16 locations with the body-up pressurecalculated during step 410. After this "packing" of ARRAY I in step 480,the sensor processing unit 101 reads the pressure at the pressuresensors 51a-d in step 490 in accordance with the same procedure aspreviously described. At step 500, that pressure value is stored in oneof the storage cells in ARRAY I, thereby replacing one of the body-uppressures "packed" into the array. From the 16 values in ARRAY I, anaverage pressure is calculated at step 510.

At step 520, the sensor processing unit 101 determines if the averagepressure calculated in step 510 is greater than the body-up pressureplus a constant. The constant is added as a buffer in order to ensurethe truck body 13 is lowered onto the tubings 47 before the programprogresses to the next step. Since initially at step 520 the ARRAY I ispacked with the body-up pressure (except for the one reading obtainedand stored during steps 490 and 500, respectively), the average pressurecalculated from ARRAY I is approximately equal to the body-up pressure.Therefore, if the average pressure is less than the body-up pressureplus a constant in step 520, the sensor processing unit 101 returns tostep 490 via step 521 where another pressure reading is made and theresulting pressure is stored into ARRAY I at step 500. With each storageof a new value in ARRAY I, the oldest value is dropped. The averagepressure is again calculated at step 510 from the values in ARRAY I andthe resulting value is compared to the body-up pressure plus a constantto determine if the truck body has been lowered onto the tubings 47.Steps 490-520 are repeated until the average pressure calculated fromARRAY I reaches a value (because of the lowering of the truck body 13)that is greater than the body-up pressure plus a constant. When thisoccurs the sensor processing unit 101 will branch from step 520 to step524 in the flowchart.

Since a negative decision in step 520 indicates the truck body is notfully resting on the on-board weighing device, step 521 checks todetermine if the truck is moving before returning the program to step490. Moving the truck with the body raised may cause serious damage tothe hinge assemblies 17 and/or the hydraulic cylinders 19 and 21. If itis determined in step 521 from the distance sensor 138 that the truck ismoving, the flowchart branches to steps 522 and 523 wherein the distancetraveled is recorded and updated and where a status flag is set for usein connection with step 524.

If the test in step 520 indicates the truck body is completely lowered,the program leaves the loop of steps 490-523 and branches to a test instep 524 in which the status flag of step 523 in investigated. If it hasbeen set, the truck has been moved before the body was fully lowered.Therefore, step 524 branches to step 525 and 526 in response to a setcondition of the status flag. In step 525, a running total is kept ofthe number of dumps for which the truck was moved before the body wasfully lowered. Step 526 resets the status flag.

In order to check for a haul-back condition--i.e., not all of the loadwas dumped--step 527 investigates the pressure from the on-boardweighing device to determine if the pressure is greater than tarepressure plus a predetermined margin. In the exemplary embodiment, themargin is seven percent of the optimum load. A determination in step 527that the average pressure is too great and a haul back condition existswill result in the printing of the operator's number by the printer 119in step 528 and/or a flashing of the operator's number on display 117(or storing this data in ARRAY VII for downloading). From steps 527 or528, the program moves to step 530 in FIG. 18e where the CPU 103 readsthe current time for use in connection with a later step.

Referring now to FIG. 18e, at step 540, the gear sensor 135 is againchecked to see if a gear shift has occurred. If it has, the programbranches to step 550 where the following information is printed by theprinter 119 (or transferred to ARRAY VII)--gear shifted from, mostrecently calculated average net weight, elapsed time in the previousgear and distance traveled in previous gear. As with step 390 in FIG.18c, the gear change in step 540 may be stored as a status flag in orderfor it to be included with the downloading of data to a central computeras discussed hereinafter. At step 560 the sensor processing unit 101determines if 25 seconds have elapsed since the time read in step 530.If it has not, the program returns to step 540 and the unit 101 againchecks to see if there has been a shifting of gears. The delay of 25seconds implemented at step 560 insures that the truck body 13 hassufficient time to fully settle on the truck frame 15 before the sensorprocessing unit 101 continues through its calculations.

After 25 seconds have elapsed, the sensor processing unit 101 movesforward to step 570 where a new net pressure reading is calculated andloaded into each of the 16 locations of ARRAY I. From the 16 netpressure readings in ARRAY I, a single average net pressure reading iscalculated at step 580. From step 580, the sensor processing unit 101branches back to the beginning of the main loop of the program at step269, flagged as "A" in the flowchart.

A periodically generated (for example, two seconds) timer interruptcauses the sensor processing unit 101 to execute the steps of thesubroutine in FIG. 18f. This subroutine determines whether an increasein current pressure is attributable to a spike (from rough roadconditions) or the addition of a bucket. If it is determined the formeris the cause of the pressure increase, the subroutine records theincrease as a spike in order to monitor road condition; alternatively,if it is determined a bucket has been added, a series of steps areexecuted to update the load status of the sensor processing unit 101.

Referring to the particular steps in FIG. 18f, an internal counter ofCPU 103 is checked in step 582 to determine if the predetermined maximumcount set in step 260 of FIG. 18a has been reached. The predeterminedmaximum count equals the number of cells in ARRAY I in order thatsuccessive average pressure values calculated in the subroutinerepresent completely different sets of pressure data. If the value ofthe counter exceeds the number of cells in ARRAY I, the program branchesfrom step 582 to step 584 wherein the current net pressure is examinedto determine if it is greater than the old net pressure reading plus aconstant. The constant is a number which is intended to identifypressure increases from the last average which are great enough to beidentified if they later prove to be pressure spikes resulting fromrough road conditions. If the current net pressure is greater than theold net pressure plus a constant, the program resets the counter at step586. Otherwise, the program branches to step 616 whose function will bediscussed later. By setting the counter to zero, the next interrupt willresult in step 582 branching to 588, instead of step 584 as before.

In step 588, the counter is increment and then examined, in step 590, todetermine if the counter has reached the maximum count (equal to thenumber of array cells in ARRAY I). If the count is less than the maximumcount, the readings in ARRAY I are not necessarily all new redings withrespect to the last average reading. Therefore, the program bypasses thecalculation of a new average net pressure and associated program stepsby branching to step 616.

If the current count equals the maximum count, then the program moves tostep 592 wherein the current average net pressure from ARRAY I iscompared to the old average net pressure plus a constant to account forhardware error from devices such as A/D converter 129 (the old averagenet pressure is the average net pressure which served as the current netaverage pressure the last time step 592 was answered yes). If thecurrent net average does not exceed the old net average, then theincrease in pressure which caused the counter to reset in steps 584 and586 must have been a spike and not a sustained increase in weightindicative of an added bucket. Therefore, the program branches to step594 wherein the size of ARRAY I is increased to 24 and the correspondingmaximum count is increased to 24. By increasing the size of ARRAY I,more readings will comprise each average thereby mitigating the effectof pressure spikes. In order to monitor the roughness of the road, thepressure spikes are recorded in step 596. From step 596, the programbranches to step 616. In step 616, the weight displayed by the LEDdisplay 117 (FIGS. 2b and 16) is refreshed. Alternatively, or inaddition to this, new weight data can be transferred to ARRAY VII fordownloading to a remote site via a radio link.

If the current average net pressure is greater than the old average netpressure plus an error factor, than a sustained increase in the load isindicated, i.e., a bucket has been added. Therefore, the load is updatedin steps 598-608. In step 598, the current average net pressure isconverted to weight in preparation for display. Because the truck isbeing loaded (as indicated by an added bucket), the truck can be assumednot to be moving; therefore, spikes are unlikely to occur. Based on theforegoing assumption the size of ARRAY I is reduced to 16 in step 600 inorder to provide more frequent averages (the maximum count is also setat 16). In order to provide an old net average pressure and an old netpressure for the next interrupt in which the count equals the maximumcount, the present average net pressure and present instantaneous netpressure are designated old pressures in steps 602 and 604.

Since the truck 11 is in the process of loading, a Load ImbalanceSubroutine is called in step 606 and a Load Analysis Subroutine iscalled in step 608. These subroutines will be discussed in detail inconnection with FIG. 18j and FIGS. 18k and m, respectively. From steps590, 608, 584, 586 or 596, the program updates the average weight shownon the display 117. Of course, if steps 598-608 have been bypassed, theupdated average weight is the same as the old average weight. After theroutine of FIG. 18f has executed its steps, the sensor processing unit101 returns to the main program of FIGS. 18a-18e.

Turning to the subroutines illustrated by the flowcharts in FIGS. 18h-k,m, p and r, each subroutine is called from the main program representedby the flowchart in FIGS. 18a-f. For the Read Pressure Subroutine ofFIG. 18h, the subroutine is called from step 270 in the main program. Inthe first step of the subroutine, a single average pressure reading isobtained in step 620 for the on-board weighing device in the mannerpreviously described. From step 620, the subroutine calculates fore andaft pressures in steps 630 and 640, respectively. In order to calculatethe aft pressure, the average pressure readings from the rearwardlypositioned sensors 51b and 51d are averaged. Correspondingly, in orderto provide a forward pressure, the pressure values from the forwardlypositioned sensors 51a and 51c are averaged. These fore and aft pressurereadings are used in connection with the Imbalance Subroutine called instep 606 and set out in FIG. 18j.

In steps 650 and 660 of the Read Pressure Subroutine, the side-to-sidepressure of the truck body on the on-board weighing device isdetermined. Specifically, in step 650, the averaged pressure readingsfrom sensors 51a and 51b on a first side of the truck 11 are averaged inorder to provide a pressure for the first side. Correspondingly, for theopposite side, the averaged pressure readings from sensors 51c and 51dare averaged. As with the fore and aft pressure readings, theside-to-side pressure readings are used in connection with the ImbalanceSubroutine of FIG. 18j. After the pressure sensors 51a-d have been readand the appropriate pressure measurements calculated, the subroutinereturns to the main program at step 275.

Referring to the Operator Summary Subroutine in FIG. 18i, dataindicative of operator performance may be gathered and stored duringtruck operation under the control of a particular operator number andthereafter summarized and displayed or printed when the operator numberis changed. Although the steps of FIG. 18i are described in connectionwith organizing data in connection with an operator number, it will beappreciated that the number, input via keypad 122, need not only beindicative of an operator change, but it may also be indicative ofchanges in truck status occurring while under the control of a singleoperator, e.g., hauling, break time and other identifiable time segmentsin a daily routine. For example, summaries in accordance with FIG. 18imay be kept for the duration of the control by an operator, but entry ofan additional number via keypad 122 may be recognized by the sensorprocessing unit 101 as identifying a loader for which summaries are alsoto be kept. When the truck is directed to a different loader, theoperator merely enters the new loader number into the sensor processingunit 101 via the keypad 122 and, in response to the number change, theunit outputs the performance summaries while the truck was loading fromthe previous loader. From the foregoing, other natural extensions ofthis concept exemplified in FIG. 18i will be obvious to those familiarwith mining management.

The flowchart for the Operator Summary Subroutine sets forth exemplarytypes of data that can be stored and summarized by the on-board weighingdevice during its normal operation. For example, since the on-boardweighing device calculates the total load for each hauling cycle, theload may be stored and accumulated for all the hauling cycles for aparticular truck operator number. By accumulating pressure readings fromthe on-board weighing device which reflect the total tonnage hauled bythe operator, useful information indicative of operator performance canbe obtained.

In order to mark the end of the time interval for which the truck wasunder the control of the previous operator number, the present time isread in step 669. In step 670, the current time or real time in step 669is designated as the "new operator time". To find the elapsed time ofcontrol under the previous operator, the old operator time is subtractedfrom the new operator time in step 671. In order to prepare for the nextoperator change, step 672 sets the new operator time identified in step670 equal to the old operator time. In step 673, the total tonnagehauled is divided by the total number of buckets (which is also countedand accummulated) in order to give an indication as to the averageweight for each bucket. The weight of the average load is found in step674 by dividing the total tonnage hauled by the total number of loads.In addition, in step 675, the total number of spikes recorded during thehauling cycles is divided by the total number of loads to provide anaverage number of spikes for the loads which is indicative of the degreeof road roughness. To provide an indication of wire tear, the subroutinecalculates a value for tons-miles per hour in step 676 by dividing thetotal "ton.mile" from step 435 by the total time under operator control.In order to display the average time for a haul cycle, step 677 dividesthe total time under operator control by the total number of loads bythe operator. To find the average distance traveled per load cycle withthe body of the truck raised, step 678 divides the total body-updistance (from step 522) by the number of body-up loads (step 525). Theforegoing data is stored in ARRAY III of RAM 107.

In step 680, the average number of buckets per load is calculated frominformation accumulated during the hauling cycle i.e., the total numberof buckets from step 790 and the total number of loads hauled by theoperator. In step 690, the average time between buckets is calculated.Since the addition of each bucket is sensed by the routine of FIG. 18f,the time between successive buckets is easily determined (in step 850).By summing the times and storing the sum in ARRAY II, the average timebetween buckets for an operator can be calculated and printed. Thisaverage will give an indication of possible problems during the loadingcycle. In step 700, the longest time interval between buckets for eachhauling cycle (from step 1020) is summed and divided by the total numberof hauling cycles to give a value indicative of the averge maximuminterval between buckets for the operator. Finally, in step 710 theaverage values calculated in steps 670-700 are printed by printer 119 inorder to give the operator and his employer a hard copy of the foregoinghauling parameters. Of course, as with the previous data outputs, thisdata may be transferred to ARRAY VII to await downloading to a centralcomputer via a radio link established by the on-board transceiver 150.From step 710, the subroutine returns to the main program at step 280.

Referring now to FIG. 18j, the Imbalance Subroutine called from step 606in the routine of FIG. 18f tests to determine if the weight distributionof the load carried by the truck body 13 is significantly imbalanced. Instep 720, the Imbalance Subroutine checks to determine if the mostrecent net pressure reading is greater than 65 percent of apredetermined maximum load pressure. If the truck body 13 has not yetbeen loaded to this percentage of its capacity, then the program willexit the subroutine and return to the main program at step 608 in FIG.18c. When the truck body has been loaded to a weight which is greaterthan 65 percent of the maximum load the Imbalance Subroutine will testfor side-to-side imbalance and fore-and-aft imbalance in steps 730 and740, respectively.

In step 730, the side-to-side balance is tested by determining if theoptimum balance ratio (i.e., 1.0) multiplied by the pressure of thesecond side and subtracted from the pressure of the first side has anabsolute value greater than, for example, ten percent of the truck'sload capacity. If the test in step 730 indicates an imbalance of theload, the subroutine activates the display 117, audio output 196 (FIG.2b) and/or printer 119 (FIG. 16) at step 750 in order to warn theoperator of the truck. This data may also be downloaded via ARRAY VII.From step 750, the program checks for fore-and-aft imbalance at step740. Alternatively, if a side-to-side imbalance is not indicated by thetest in step 730, the subroutine branches directly to step 740 where aalgorithm similar to the algorithm in step 730 is utilized to test for afore-and-aft imbalance. (The optimum ratio for fore-to-aft balance maybe, for example, -3 to +3.) If a fore-and-aft imbalance is indicated instep 740 the program moves to step 760 wherein the display 117 inbalancesignal 197 (FIG. 2b) and/or printer 119 (or other indication such astruck mounted light 197 to alert loader operator) is activated to alertthe truck operator that the truck body is loaded in an imbalancedcondition which may cause damage to the truck (this data may also bedownloaded via ARRAY VII). From the Imbalance Subroutine, the programmoves to the Load Analysis Subroutine.

Referring now to FIG. 18k, the Load Analysis Subroutine provides datarelated to the loading of the truck body by a loader using a bucket toload the body. By analyzing and summarizing data related to the bucketswhich incrementally load the truck body, useful information regardingthe efficiency of the hauling cycle can be obtained. The Load AnalysisSubroutine is called from the routine of FIG. 18f if it is determined atstep 592 that the current average of the net pressure readings in ARRAYI is greater than the old average net pressure plus a predeterminedconstant. As explained in connection with FIG. 18f, when the currentaverage of the net pressure readings in ARRAY I is greater than the oldaverage of the net pressure plus a constant, it can safely be assumed abucket has been added to the body of the truck; therefore, the LoadAnalysis Subroutine will be executed starting at step 770 wherein a newbucket pressure is calculated by subtracting the old average netpressure from the current average net pressure.

In step 780, an average value for the bucket pressure for this load iscalculated by multiplying the previous average bucket pressure per loadby the number of previous buckets per load and adding the product to thenew bucket pressure calculated in step 770. The foregoing sum is thendivided by the number of buckets per load which is the number ofprevious load buckets plus one. In steps 790 and 800, the subroutineupdates the number of total buckets and the number of buckets for thecurrent hauling cycle, respectively. In steps 810-815, the time of thebucket is recorded for use in connection with steps in the Load AnalysisSubroutine to be discussed hereinafter.

In step 820 of the Load Analysis Subroutine, a test is conducted todetermine if the current bucket is the first bucket of a hauling cycle.If the current bucket is the first bucket of a hauling cycle, theprogram branches to steps 825-829 before returning to the main programloop at step 616 in FIG. 18c. For use in connection with latercalculations related to bucket loading time and total buckets, step 825renames the "new bucket time" as the "old bucket time" and initializesARRAYS V and VI of RAM 107. For use in connection with communicatingwith a central computer for controlling the flow of the truck fleet, aload flag is set in step 827. This flag is used in connection withtransmitting data from the on-board weighing device to a centralcomputer as will be explained in greater detail in connection with FIGS.19-20. Finally, in steps 828 and 829, a fresh ton.mile rating is takenwhich corresponds to the ton.mile rating for the haul segment from thedump site to the load site.

If the current bucket is not the first bucket of a hauling cycle, theprogram branches from step 820 to steps 830-860. In step 830, acalculation is made of the elapsed time between the addition of thecurrent bucket and the time at which the previous bucket was added atstep 830. In step 840, the bucket times are updated in order to preparethe data for the next bucket. In step 850, the elapsed time between thecurrent bucket and the previous bucket is added to a running total oftime intervals between buckets to provide a total elapsed loading time.This total elapsed loading time is used in connection with step 690 ofthe Operator Summary Subroutine in order to provide data indicative oftruck and operator performance.

In order to store the net pressure of each bucket, step 852 loads ARRAYV with the pressures for all the buckets of a current load cycle. Thelast cell, N, in ARRAY V is used as a storage location for the value ofthe average bucket weight for a load. In connection with the storage ofthese pressures, step 855 stores the elapsed time between the additionof buckets in a load cycle in ARRAY VI. The data in ARRAYs V and VI maybe used in connection with providing a detailed performance report ofeach load cycle.

In step 860-885, the longest elapsed time between buckets is found. Instep 860, the program tests to determine if the current bucket is thesecond bucket. If the current bucket is the second bucket, then theprogram automatically designates the current elapsed time betweenbuckets as the maximum elapsed time between the buckets in step 870.Alternatively, if the current bucket is not the first or second bucketas determined in steps 820 and 860, the program will branch to step 880wherein the current elapsed time between buckets is tested to determineif it is greater than the maximum elapsed time between bucketspreviously recorded. If the current elapsed time between buckets is notgreater than the previously recorded maximum elapsed time betweenbuckets, the program branches to step 890 (FIG. 18m); otherwise, theprogram designates the elapsed time between buckets as the new maximumelapsed time between buckets at step 885. The maximum elapsed time isused in connection with step 700 of the Operator Summary Subroutine.

Referring now to FIG. 18m, the current average net pressure is tested toindicate whether the load of the truck body is sufficiently close to themaximum load capacity of the truck such that further addition ofmaterial by a full bucket would overload the truck body. In order toprevent the truck from being overloaded, steps 890-920 test to determineif the remaining capacity of the truck body 13 is less than the weightof an average bucket for this load as calculated in step 780 of thesubroutine.

Specifically, in step 890 the average net pressure is compared with thepredetermined maximum of the truck body minus one-quarter of the averagebucket. If the average net pressure is greater than the maximum loadminus one-quarter of the average bucket, the truck body will beoverloaded by the addition of as little material as fills one-quarter ofthe bucket. Therefore, the subroutine branches to step 895 wherein thered light 140e of the load indicator panel is activated. The red light140e serves to warn the loader operator that the truck body 13 is loadedto a capacity which any further loading would overload the truck body.

If the average net pressure is not greater than the maximum load minusone-quarter of the value of an average bucket the subroutine moves tostep 900 wherein the current average net pressure is compared with thepredetermined maximum load minus one-half the value of an averagebucket. If it is determined that the current average net pressure isgreater than the maximum load minus one-half the average bucket, thesubroutine branches to step 905 wherein the one-quarter yellow light140d of the load indicator 140 in FIG. 16 is activated. For the loaderoperator, the one-quarter yellow light 140d indicates that the loadermay add further material to the truck body 13 but only an amount lessthan one-quarter of the volumetric capacity of the bucket of the loader.

If the test in 900 determines that the average net pressure is notgreater than the maximum load minus one-half the average bucket, thenthe subroutine tests at step 910 to determine whether the currentaverage net pressure is greater than the maximum load minusthree-quarters the value of the average bucket. If a positivedetermination is made in step 910, the subroutine branches to step 915wherein the one-half yellow light 140c is activated on the loadindicator 140. In a similar manner as the one-quarter yellow light 140d,the one-half yellow light 140c indicates to the operator of the loaderthat the next bucket of material must fill the bucket no greater thanone-half the volume of the bucket in order to avoid overloading thetruck 13.

If the test in step 910 is negative, the subroutine tests to determineif the current average net pressure is greater than the predeterminedmaximum load minus a full average bucket. If the test in step 920 ispositive, the subroutine activates the three-quarter yellow light 140bof the load indicator 40 in step 925. If the test step 920 is negative,the green light 140a of the load indicator 140 is activated in order toindicate to the operator of the loader that a full bucket load ofmaterial may be added to the truck body 13 without overloading the body.From steps 890-926, one of the lights 140a-e on the load indicator 140will always be activated during the loading of the truck body 13.

Digressing briefly to FIG. 16, the lights 140a-e of the load indicator140 are positioned in a stacked arrangement such that there relativepositions give an indication of the degree of remaining truck capacity.Specifically, the green light 140a occupies the lowermost position inthe stack of lights 140a-e, thereby indicating that the truck body hascapacity for a full bucket load. The red light 140e at the top of thestack, indicates the truck body is full and no further bucket loads cansafely be added. The three lights 140b-d are positioned intermediate thegreen and red lights in order to indicate weight capacities intermediatethe full bucket capacity symbolized by the green light 140a and noremaining capacity symbolized by the red light 140e.

Referring now to FIG. 18p, the Axle Load Analysis Subroutine is calledfrom the main program at step 305 when a determination is made in step304 that the operator has called for an analysis of the axle load. Asexplained in connection with the illustration of FIGS. 13a and 13b, thepressure in the hoist cylinders 19 and 21 is required to calculate thedistribution of the load between front and rear axles. Accordingly, instep 928 the pressure from sensor 139 (FIG. 16) is read by the CPU 103and converted to a weight measurement. In order to get a total bodyweight, the weight of the load derived from the current average pressureis added to the tare weight of the truck body in step 929. In step 930the center of gravity for the load is calculated from the total weightand the weight measurement from the sensor 139 in the hoist cylindersystem. The particular algorithm used in step 930 in order to calculatethe location of the center of gravity for the load is set forth asequation 2 in connection with FIGS. 13 a and 13b. With the center ofgravity for the load known, the distribution of the load over the frontand rear axles is determined in steps 940 and 950, respectively, usingequations 4 and 6.

In step 960 the tare weights for the front and rear axle are added tothe axle loads for the front and rear axles calculated in steps 940 and950. Therefore, the adjusted pressure readings for the front and rearaxles obtained from step 960 reflect a total weight over the front andrear axles. Finally, in step 980, the subroutine commands the printer119 to print the weights bearing on the front and rear axles (or storein ARRAY VII).

Turning now to FIG. 18r, the Dump Subroutine is called by step 406 ofthe main program after the dump sensor has been activated as detected instep 400. The Dump Subroutine summarizes selected parameters at the endof a hauling cycle which is indicated by the activation of the dumpsensor 137. In step 1000, the current average net weight is added to thetotal of previous weights hauled in order to provide the total tonnagehauled by the truck while under control of the operator. The totaltonnage hauled is used in connection with the Operator SummarySubroutine. Because the activation of the dump sensor 137 indicates anend to a hauling cycle, the number of buckets per load and the averagebucket pressure per load are set equal to zero in step 1010 in order toinitialize these values for the next hauling cycle. In step 1020, atotal maximum elapse time between buckets is updated by adding themaximum elapsed time between buckets for the last load cycle.

In order to record the number of hauling cycles, step 1030 increments astored number identified as "total number of loads" which is used inconnection with the Operator Summary Subroutine to provide averaged dataindicative of operator performance. In order to keep track of roadroughness, the total number of spikes recorded during a hauling cycle isaccumulated in step 1040 with the number of spikes during previoushauling cycles. The total number of spikes is used in connection withthe Operator Summary Subroutine in order to provide an indication ofroad quality. Following step 1040, spikes are set equal to zero in orderto provide a frsh basis for accumulating spikes in the next load cycle.

In step 1050, a test is conducted to determined whether the currentaverage net pressure is greater than a predetermined maximum pressurewhich corresponds to the maximum weight capacity of the truck. If thetest in 1050 is positive, the overloading of the truck is recorded insteps 1060-1080. In step 1060, an overload counter is incremented toindicate that the present hauling cycle was an overload cycle. In step1070, the amount of overloading or "overage pressure" is calculated bysubtracting the average net pressure from the maximum allowablepressure. The average pressure for the present hauling cycle is added toa total overage pressure for all hauling cycles in order to provide apressure value indicative of the total weight by which the truck hasbeen overloaded. From either step 1080 or from a negative indication instep 1050 the Dump Subroutine moves to step 1090 wherein the printer 119(FIG. 16) is activated to print the weight of each bucket for the justcompleted haul cycle (stored in ARRAY V) and the elapsed time betweeneach bucket (stored in ARRAY VI). This data may also be transferred toARRAY VII for downloading.

As is apparent from the foregoing description, large amounts of data aregathered from the on-board weighing device and related on-board sensors.When a plurality of trucks in a fleet are equipped to collect such data,in order for this data to be of the most benefit to fleet operators,this data needs to be downloaded for long term storage and analyzationin order to create and maintain a historical file of truck fleetactivity and performance. Obviously, the printer 119 provides apermanent record. However, for large fleets it is cumbersome, at best,to store this data in this form with an intent of later analyzation andreference. Therefore, to allow the data generated to be more easilymanipulated and analyzed, the sensor processing unit 101 may be coupledto a storage memory such as a cassette tape or non-volatile memory packin order to download the ARRAYS when they reach their capacity. However,downloading in this manner is not on a real time basis and it requiresoperator or management intervention in order to assure the downloadeddata is collected in a timely manner i.e., collection of paper tape.

For the data generated by the sensor processing unit 101 to be of thegreatest benefit and value it needs to be gathered and analyzed on areal time basis (as opposed to gathering paper tapes at the end of awork cycle) so that as data is generated by a fleet of trucks it can beimmediately gathered to provide a real time analysis of fleetoperations. Therefore, preferably, and in accordance with the invention,the accumulating real-time data can be of the most value if it isdownloaded by a radio link from the on-board device to a remote fixedlocation where a historical real-time file can be created and analyzedin order to give management personnel at a remote site a currentindication of truck fleet performance. By analyzing the downloadedreal-time data on a historical real-time basis, the loaders of thetrucks may also be evaluated. As a feature of the real-time datagathering by radio link data downloading, each truck in a fleet is ableto communicate with a central computer via radio links with one or morerepeater points. As this occurs, these repeater points can in turncommunicate back data from the central computer to the individualtrucks; Therefore, instructions/directions can be sent selectively totrucks.

Referring to FIG. 19a, in mining operations or similar type hauling, itis not unusual for there to be simultaneously hauling of overburden,coal or the like. Also, in large operations, more than one loader 160services the truck fleet and there may be more than one dump site.Gathering data generated by the sensor processing unit 101 andcontrolling traffic flow from the dump sites to the loaders 160 orvis-versa becomes unwielding, and therefore inefficient, when the miningoperation is large and many trucks and loads are involved. As a functionof its data gathering capabilities, the on-board weighing systemdescribed herein allows the electronic system of FIG. 16 to accuratelyrecord the elapsed time of a hauling cycle or segments thereof and,since the on-board weighing system provides an indication to theelectronic system when a load cycle begins and ends, as a transceiver150 is mounted to each truck 11 (illustrated in FIG. 19a) for datadownloading with a central computer 155. This data when gathered by thecentral computer 155 and analyzed can be utilized by the centralcomputer to provide instructions and directions for efficient trafficcontrol and remote monitoring of truck performance. Other data, inaddition to the above, as outlined in the flowcharts of FIGS. 18a-r isalso downloaded to the central computer 155 for storage and analysisfrom the on-board weighing device. As will be explained in greaterdetail hereinafter, data downloading communication between the trucks 11and the central computer 155 is handled by strategically locatedrepeaters 160a and 161 in FIG. 19a.

The central computer 155 receives data from the electronic circuitry onthe truck 11 by way of the radio (or hard wire) links 157 (or hard wirelinks from stationary pick up points such as dump sites). In order toprovide a two-way link, the central computer 155 includes a transceiver155a. Data received from the trucks 11 is processed by the CPU 155b withthe aid of PROM 155c and RAM 155d. The CPU 155b communicates to the PROM155c and RAM 155d along a bus 155e in conventional fashion.

Because the on-board weighing device and its associated circuitrydetermines when a load cycle starts (the first bucket is sensed) andends (first gear shift after first bucket) and when a dump begins (aswell as other operating data), the central computer 155 is able to usethis data to provide efficient instructions and directions forcontrolling movement of the trucks without depending on any humancooperation, e.g., no one need remember to manually hit a load or dumpswitch to signal the central computer. Because the system is fullyautomated, it is highly reliable. In addition, the data gathered byreal-time radio data downloading from the on-board weighing device, whenstored and analyzed by the central computer, allows precise control ofthe routing of the trucks for top efficiency.

Referring to FIG. 19b, by way of transceiver 150 the trucks 11 downloada data frame comprising a synchronization word followed by the trucknumber and data representative of a truck condition, e.g., a load ordump condition. In response to this received data from the trucks 11,the central computer stores and analyzes this data. After the centralcomputer properly analyzes this data it may, depending on truck status,send a data frame comprising a synchronization word followed by theparticular truck and loader numbers. In order to prevent simultaneous oroverlapping transmissions from the trucks 11, the trucks 11 transmit inresponse to an inquiry signal from the central computer 155. The centralcomputer 155 polls the trucks 11 to determine if any truck is ready tosend data. In response to a polling, the trucks 11 response bytransmitting the required data (dump, load or other data) in the formatshown in FIG. 19b.

Keying the transceiver 150 for transmission of the data frame occurs inresponse to the sensing of data generation such as a dump condition(activation of the dump switch 137) a load condition (sensing of a firstbucket) and the like. Obviously, whether the data frame includes load ordump data indications depends on whether the dump switch 137 has beenactivated or whether a first bucket has been added. As will be explainedin greater detail in connection with FIGS. 20a-b, the central computer155 receives the data in the data frame from the trucks 11 and concludesfrom the data which loader 160 can provide the quickest load cycle timefor a truck now dumping and therefore ending its previous load cycle orwhich dump site is the proper one for a truck now loading and thereforeready for instructions and/or directions to a dump site. Once thecentral computer 155 has determined which loader will minimize the timeof a load cycle or which dump site is the proper one, the computertransmits by way of transceiver 155a the data frame containing aparticular truck number the computer wishes to address and a particularloader or dump site number which the computer wishes to direct thetruck. Each truck receives the data frame from the central computer 155,but only the truck having the same number as the number transmitted withrespond to the data containing the loader number. When the truck numberand the truck number data correspond, the loader dump site or other sitedesignation number transmitted with the truck number is either displayedon the LED display 117 of the designated truck or printed as hard copyon the truck's printer 119. From the loader number, the truck operatorknows which loader to go to for his next load. By analogy, the centralcomputer 155 may also deliver destination data when multiple dump sitesare used or a rest stop designation if the operator is scheduled for abreak. Many other useful destinations will be appreciated by thosefamiliar with mining operations.

Referring briefly to FIG. 19c, an opening 1300 may be provided in thefloor of the body 13 for allowing a switch assembly to sense thepresence of a load and thereby indicate to the sensor processing unit101 when loading begins. Such a device could combine with the sensorprocessing unit 101 to give a simplified truck dispatch system accordingto FIG. 19a. With the addition of the switch assembly of FIG. 19c, theon-board weighing device and its complementary load sensors (except thedump sensor) are not required for simply dispatching trucks in responseto load and dump signals only.

The opening 1300 in the floor of the truck body 13 is covered by aflexible, but rugged material 1301 such as a thick rubber mat which issecured to the bed of the truck body along its perimeter. A hinged flap1302 is biased upwardly by a spring and shaft assembly 1303. In responseto the introduction of material into the truck body 13, the flap 1302closes over the opening 1300 and pushes down the plunger of a switch1304. Of course, the switch closure generates a signal indicative to thesensor processing unit 101 of the starting of loading.

In the flowchart of FIG. 20a, the data received from the trucks 11, ismanipulated and stored in order to accurately determine the correctloader to route a truck when it completes a haul cycle. A periodicinterrupt causes the central computer to execute the steps of FIG. 20a.At each interrupt, the central computer 155 polls all the trucks 11 fordata. In step 1097, the present time is read and temporarily stored. Instep 1098, the truck number is initialized to a starting value. Thetransceiver 155a is keyed in step 1099 and a formated inquiry signal issent to the designated truck. If data is detected in step 1100, thecomputer reads the data and manipulates it in accordance with steps1110-1190; otherwise, the truck number is incremented in step 1102, anda new truck is polled for data in step 1099. If all the trucks have beenpooled for this interrupt, step 1104 returns the central computer 155 tothe main program. When a valid transmission is detected, the flowchartmoves to step 1110 where the truck number is decoded. If the receiveddata frame includes a dump indication, the most recent load time forthis particular truck is subtracted from the current time to provide aloaded haul time in step 1140. If a dump indication is not present, theprogram branches to step 1132 where the data frame is checked for a loadindication. If the data frame includes a load indication, the programbranches from step 1132 to step 1135 wherein the real time is stored asthe "load time". If a load indication is not present, step 1132 returnsthe central computer 155 to the main program. By analogy, otherdownloaded data (gearshift, operator number change, etc.), may beidentified by the central computer 155 and routed to appropriate storagelocations at the central computer. Of course, data of different types(e.g., elapsed times, weights of buckets, etc.) must be encoded in aconventional manner by the sensor processing unit 101 in order that thecentral computer 155 can identify the data for categorization.

At the central computer 155, a data base (not shown) is maintained foreach truck as well as for each model of truck. For example, in a fleetof 20 trucks, trucks one through 10 may be a first type of truck with aparticular capacity, while trucks 11-20 may be a second type of truckwith a different capacity. From the makeup of the truck fleet, a database is organized to best provide useful information. For theabove-mentioned fleet of 20, the data base is divided into two mainsections, one for each type of truck, and each section has ten cells,one for each truck. By organizing the data base in the foregoing manner,data for each truck can be collected and manipulated and, also, data foreach type of truck can be obtained. In addition, since each haul cyclefor a truck is identifiable with a particular loader, a data base isalso set up for each truck/dump site/loader combination.

In the data base at the central computer 155, the cell for each truckincludes data identifying the last loader to which the truck wasdirected and the time it was directed. Therefore, an average loaded haultime for a particular truck hauling from a particular loader to aparticular dump site can be determined. In step 1150, an average haultime for each of the trucks from each of the loaders to each dump site,stored in an array in RAM 155d, is accessed. The most recent haul timefor a particular loaded truck, a particular loader and a particular dumpsite is added to the average in order to update it in step 1160. Theupdated average loaded haul time is returned to the storage array instep 1170.

Because the central computer 155 is in communication with each of thetrucks 11, it knows the number of trucks 11 that have been sent to aparticular loader; it also knows how many of those trucks sent to aparticular loader 160 have indicated loading has begun. From theforegoing information, as the trucks 11 become available from a dumpsite or other areas, the central computer 155 executes an algorithm instep 1180 to determine which loader can most quickly load the currenttruck and return it to the dump site. The central computer 155calculates a "delay" time for each loader and identifies the loader withthe minimum delay as the truck's destination. For each loader 160 thedelay may be determined as follows: ##EQU7##

From the foregoing algorithm, the central computer 155 calculates in aconventional manner from available data the number of trucks in transitto or at the loader (n). A calculation of the number of trucks at theloader site or in transit thereto is easily derived from available datasince the central computer 155 identifies which trucks have beendirected to a given loader 160 and have not yet transmitted a load startsignal. The load time of each loader is calculated from data madeavailable by the truck's sensor processing unit 101. The beginning ofthe load is marked by the central computer 155 when it receives a loadsignal from the sensor processing unit 101. The end of the loading ismarked by the central computer 155 when it receives the first gear shiftsignal sensed by the sensor processing unit 101 from the gear sensor 135after transmission of the load start signal to the central computer 155.Obviously, for the central computer 155 to calculate a load time and anaverage load time for each loader, the on-board weighing device musttransmit both the load start signal and a signal indicative of the firstgear change. The latter signal is not set forth in the flowchartdiagrams, but it will be appreciated by a programmer that the data maybe transmitted in response to a polling request from the centralcomputer 155.

Because the loading is sequential (i.e., each truck 11 is fully loadedin its turn), only the latest load transmission signal can be from atruck still being loaded. Therefore, more than one load transmissionsignal indicates some trucks are in transit back to the dump site.Obviously, these trucks need not be considered in calculating a timedelay for loading. In order to accurately account for the time delaycaused by the truck currently being loaded, the time difference betweenthe last load signal and the average load time should be subtracted fromthe product of the number of trucks at or in transit to the loader andthe average load time. To this difference is added the travel time forthe truck being directed from that truck's present location (normally adump area) to the particular loader 160. For example, two loaders mayhave load delays of five minutes and ten minutes, respectively, beforeconsidering truck travel time. However, if the travel time to the firstloader 160 is 12 minutes while the second loader has a five minutetravel time, this travel time is subtracted from the time delay toarrive at a total delay time which is -7 minutes for the first loaderand +5 minutes for the second loader; thus, the central computer 155designates the first loader as the truck's destination since the minusdelay time indicates the time the loader will be waiting for a truck.After the delay of each loader 160 is calculated, the central computer155 transmits a signal at step 1190 having data identifying theparticular truck for which the transmission is intended and also havingdata indicating the particular loader number with the current minimumdelay time.

In response to the transmissio from the central computer 155, thetransceivers 150 of all the trucks 11 lock onto the signal during thesync portion of the transmission and compare the transmitted trucknumber to their own numbers. FIG. 20b illustrates the flowchart toexecute the comparison of a transmitted truck number and the storedtruck number. In a simple scheme, the steps of FIG. 20b are executedperiodically by a timer interrupt. At each interrupt, the CPU 103 ofFIG. 16 checks to see if the transceiver 150 is receiving atransmission. If no signal is present in step 1210, the program returnsthe CPU 103 to the main program. If a signal is present, the transmittedtruck number is captured and compared to the truck's own number at step1220. If they are not identical, the data identifying a particularloader number, dump site or designated site, which follows thetransmitted truck number, is ignored. When a match occurs between trucknumbers, the central computer 155 is contacting a particular truck 11either to poll it or to instruct it which loader 160, dump site 161 ordesignated site to go to. In order for the sensor processing unit 101 toknow which instruction is currently being received, step 1225 determinesif the data following the truck number is a polling request. If it is apolling request, the program determines at step 1240 if ARRAY VIIcontains data for downloading; if it does, the transceiver 150 is keyedand the appropriate data (e.g., dump, load gearshift, operator numberchange, etc.) is transmitted to the central computer 155 in step 1250.Alternatively, if the received data is not a polling inquiry, it must beinstructions for a loader, dump site or other destination. Therefore,the loader number, dump site or other designation is stored anddisplayed to the truck operator at step 1260.

In a haul cycle there are two important travel segments--the loader todump site segment and the dump site to loader segment. These twosegments are the main components of a full cycle. Because the on-boardweighing device detects when loading begins and when dumping occurs,important data can be transferred at those times from the truck 11 tothe central computer 155 for processing when the truck is polled. Forexample, the ton.mile calculation by the sensor processing unit 101 isimportant for each haul segment since it indicates a degree of tire usefor the haul segment. This data may be transmitted to the centralprocessor 155 for processing in response to polling of the trucks.Management personnel can monitor (the central computer 155 may,alternatively, include a software routine to monitor this or other data)the updated or averaged ton.mile data from each haul segment at the siteof the central computer 155 in order to dispatch trucks in a manner toensure even fleet accumulation of ton.mile and/or ensure tires are notbeing used above their rated ton.mile per hour rating. Of course, otherdata available from the on-board weighing device can be downloaded tothe central computer 155 in the same manner as the foregoing data.Finally, a portion of the data downloaded to the central computer 155may, in addition, be downloaded to a processor (not shown) on-board theloader 160 loading the truck in order to give the operator of the loaderan indication of the truck's load condition. Such a communication linkwould be similar to the link set forth above in connection with thecentral computer 155. The specific type of radio link could be any typeof commercially available data link suitable for transfer of the type ofdata here involved such as REPCO, Inc., RF modem, RDS-1200, 944-960MH_(z), full duplex. It will be appreciated from the foregoing that datasuch as the operator summaries of ARRAY II will be downloaded from thememory of the sensor processing unit 101 to the central computer 155 forstorage and analysis.

In order to reduce the expense of providing high-power transceivers oneach truck 11, for data downloading stationary repeaters 160a and 161(in FIG. 19a) are provided at scattered locations in the working site.By providing these repeaters 160a and 161, each transceiver 150 need beonly a low power device. In addition, by methods well known in the fieldof communications, the central computer 155 may identify which repeater160a and 161 is retransmitting the downloading of truck data. By knowingthe particular repeater 160a and 161 in which a truck 11 is in range,the central computer 155 may track movement of the trucks. Moreover,during data download polling of the trucks 11 by the central computer155, data may be transmitted indicating an "out-of-service" condition oran "in-transit" condition for the truck. By providing data such as theforegoing, the central computer 155 may keep track of which trucks arecurrently loading, dumping, in transit or out of service. As trucks 11are directed to various loaders 160, dump sites, etc., the centralcomputer 155 notes a projected time of arrival for the truck based onits historical data base. If a truck 11 fails to arrive at itsdesignated location within this time period plus a predeterminedpercentage of the period, then the central computer 155 will provide asensory alert ot management personnel so that the status of the truckcan be checked. For thos trucks 11 which go out of service, the centralcomputer 155 can update the load delay for the particular loader 160 forwhich the out-of-service truck was destined.

As an extension of the foregoing data downloading and controlling oftruck movement, the interaction of the sensor processing units 101 ofthe trucks 11 and the central computer 155 also provides the ability fordata file management at a remote location. Specifically, informationfrom each of the sensor units 101 is downloaded to a master data fileassociated with the central computer 155 where the data may bemanipulated in order to provide useful real time information tomanagement personnel. For example, from real time data the centralcomputer 155 may analyze the average number of loads or tons loaded perhour by a particular loader 160 and/or average number of loads or tonshauled by a particular truck. From the foregoing analysis, accurateprojections for the best utilization of the trucks and loaders can bedeveloped.

In addition to receiving the downloaded data and dispatching trucks 11to proper loaders 160, dump sites or designated sites, the centralcomputer 155 maintains data on tonnage loaded by particular loaders,tonnage hauled by particular trucks and total tonnage hauled to eachdumping area. The central computer 155 records the out-of-service timesfor all truck 11 and loaders 160 and identifies the trucks and loaderswhich are out of service for the longest times in a predetermined timeperiod.

Mine management with this system can see what has been done in terms ofmine production and can make extremely accurate projections, 1 month, 6months, possibly even 12 months down the road. With these projections asto what total mine production can be, e.g., anticipated tons of variousmaterial to be moved, the mine operating personnel can make equipmentassignments and changes to those equipment assignments so that mineproduction does, in fact, meet mine production projections.

For example, the central computer 155 cumulatively records ton-mile perhour data over a given time frame so that as a truck accumulateston-mile per hour figures the cumulative figures for all trucks arecompared and the trucks with excessive ton-mile per hour numbers can bedispatched to locations from which less ton-mile per hour figures occur.

Additionally, the central computer 155 as well as the sensor processingunits 101 may analyze vehicle component strain, such as engine operatingtemperature, hydraulic oil temperature, heat buildup in the tires, etc.As a particular component on a vehicle approaches a preset limit, thevehicle may on future haul dispatches be dispatched to a haul that mightbe less trying on the vehicle, i.e., for a mine with a multi-benchoperation vehicles may be rotated so that no one vehicle is continuallyhauling off of the lowest bench. This analyzation of vehicle componentstrain obviously turns on the need to add additional vehicle monitors tothe vehicle and provide radio downloading transmission capabilities fromthese monitors to the central computer 155.

Conceptually, the master data file (not shown) of the central computer155 contains four primary files from downloading data:

(1) Loading time for each truck with each piece of loading equipment;

(2) Loaded haul time for each loader to each dump area for each truck;

(3) Empty return time from each dump area to each loader for each truck;and

(4) Total haul cycle time for each truck from each loader to each dumparea. This master data file may be either separate from or incorporatedwith the data base for each type of truck (having subfiles for eachtruck) and for each loader/dump site combination.

Each of the four primary files of the master data file is separated byloading equipment type, truck type and dump site, e.g., make, model,size, type of body or type of material to be hauled, whether it is ore,overburden, dual purpose, etc. For example, data for 170 ton trucks arefiled separate from data for 120 ton trucks. Each class of truck, loaderand dump site combination has a separate historical subfile to be usedto determine how long it should take a truck of that class to get from adump to loading site or vis versa. With respect fo the loaders 160, asimilar subfile system exists for each class. In addition, loader 160has a subfile for each type of truck it loads. These subfiles storehistorical data on how long it takes the loaders 160 to load anyparticular type of truck 11.

As a particular example of the data base and master data file, if a minehad 10-170 ton Wabco trucks and 10-120 ton Euclid trucks, then thecentral computer 155 would have a data base comprising a historicalsubfile for each truck, loader/dump site combination, i.e, 20 trucksubfiles. Data from the 10 Wabco subfiles is averaged together tocomprise a master Wabco data file; likewise, a master Euclid data fileis created for the Euclid trucks. Then, as each respective truckgenerates data, its corresponding historical subfile is updated andaveraged according to that data. In response to downloading data forupdating of these historical subfiles for each truck, the four primaryfiles of the master data file for the truck class (e.g., Euclid orWabco) are also updated.

As evidenced by the degree and variety of data available from theon-board weighing devices, the downloading communications link betweentrucks 11 and the central computer 155 is potentially much more than aRF data downloading link, it is also the means for a traffic controller.Downloading of all or selected portions of data generated by the sensorprocessing unit 101, allows the central computer 155 to function as amine management system. The following description of the functioning ofsuch a system is intended as an outline of the programming steps madepossible by the organization of memory in the central computer 155 intoa data base with subfiles for each truck/loader combination and primaryfiles for each class of truck as described herein and the downloading ofdata in addition to load and dump data as previously discussed inconnection with FIGS. 19a-b and 20a-b.

In order for polling by the central computer to occur sufficiently oftenso that the downloading of data may approach a real time data read out,repeaters 161 should be of sufficient number in strategic positions. Inaddition, by identifying their location in the repeated signal, therepeaters 160a and 161, identify truck locations, i.e. the data signalfrom the trucks 11 when received by the repeater is supplemented withdata identifying the repeater. As data accumulates in each of the sensorprocessing units 101 of the trucks 11, it is stored in memory until thetruck is within range of a repeater 160a or 161, whereupon the data isdownloaded to that repeater and sent on to the central computer 155.With strategically placed repeaters 161, not only is the data downloadedat close to a real time basis, but the repeaters keep an accurate trackof truck location.

For example, as a truck 11 leaves the dump area 1, it is notified by thecentral computer 155 via the repeater 161 at dump area 1 which loader160 had the minimum delay. The truck 11 is then on its way to thatparticular loader location. The truck 11 possibly accumulates some datain route to that particular loader 160a. As it comes within range of theparticular loader 160a, data accumulated enroute from dump area 1, ifnot previously transmitted, is transmitted to the repeater 160a on theloader and resent to the central computer 155, thus identifying thetruck's current vicinity.

As soon as the central computer 155 detects data downloading from thetruck through the repeater 160a at the loader location to which thetruck was dispatched, it knows that the truck has arrived in thevicinity of the particular loader. If in route to the designated loader,the truck 11 passes another loader 160 or comes within the range ofanother strategically placed repeater 161 (possibly dump area 2 in FIG.19a), any data accumulated is downloaded via that repeater 161 to thecentral computer 155, thereby again identifying truck location.

Once the truck 11 gets to its designated loader 160 or loading area, thegearshift is placed in neutral or reverse by the driver. This change ingear is detected by the gear sensor 135 of the on-board weighing deviceand the data is downloaded via the repeater 160a to the central computer155, and the central computer thereby has further confirmation that thetruck 11 has arrived at the designated loader. It should be noted,however, that if there are two or more loders in the same immediatevicinity or within the transmit range of the radio signal of the truck,these loaders should be classed as one loading area or one piece ofloading equipment for purposes of data handling by the central computer155.

With the truck 11 in the general area of the designated loader 160, asthe truck positions itself for loading (i.e., shifts foward, reverse,etc.), data is generated that is downloaded via the repeater 160a to thecentral computer 155 and, with the first bucket pass into the truck,additional data is generated that is downloaded to the central computer155. With the first bucket pass, the central computer 155 looks at oneof the primary files in the master data file for the average loadingtime of this particular loader 160 for loading this particular type oftruck 11. Based on this primary file, the central computer 155determines when this truck 11 will be fully loaded and when the nexttruck is needed at this particular loader 160 for continuous truckloading to occur.

With the last bucket pass into the truck 11, (sensed by a gear shiftforward leaving the loading area) this data is downloaded to the centralcomputer 155 which accesses another primary data file from the masterdata file; this file contains the average travel or haul time of thisparticular type of truck from this loading location to various dumpareas that this truck can be directed to. The central computer 155 thenanalyzes the projected truck arrival time at each of these areas basedon its record of trucks already enroute to the dump areas and determineswhich dump area will have the least congestion. The central computer 155then analyzes trucks enroute and their projected arrival times to directthe truck just loaded to a particular dump area as designated by thecentral computer as well as determining what the elapsed time shouldapproximate from this final bucket pass (i.e., gear shift forward) untilthe truck arrives at the designated dumping area. As the truck 11 leavesthe area of the loader 160 for the dump area, data (such as gearshifting, distance traveled, etc.) accumulates and is transmitted fromthe truck via the repeater 160a on the loader to the central computer155, and the central computer 155 estimates when this truck will arriveat its designated dump area.

Upon coming within range of the designated dump area, the repeater 161receives any data accumulated by the truck 11 and downloads it to thecentral computer 155. With the travel time of the truck 11 from theloading area to the dump area noted by the central computer 155, theappropriate primary file of the master data file is updated. (Loadedtravel time is the time from the first forward gear shift after loadingcommences until the dump switch is activated.) As the truck dumps, thedump switch is activated and data indicative of this is generated by thesensor processing unit 101. This data is downloaded to the centralcomputer 155 and, at this point, the truck 11 is then available foranother load. Therefore, the central computer 155 searches to determinewith what loaders 160 this particular type of truck is being used. (Thecentral computer 155 differentiates between trucks of different loadtypes-different body styles; for example, trucks hauling coal oroverburden in a mining operation.) The central computer 155 reviews theloading/haulage status of each loader 160 and, it analyzes when eachloader will need another truck to load based on (1) the historicalloading data files, (2) what trucks 11 have already been dispatched toeach of the loaders 160 and (3) the historical empty travel time fromthe particular location of the truck 11. The central computer 155 thenreviews the primary travel time file from the dump area (the truck'sparticular location) to each particular loading area. From the traveltime data, the central computer 155 looks at the historical empty returntruck time and determines which loader will need a truck the soonestand, in response to this determination, transmits directions andinstructions to the truck dispatching it to the particular loader.

At the same time that loader destination information is transmitted to atruck 11, the central computer 155 reviews a historical data file oftotal haul cycle time for that truck from the loader to which the truckhas been dispatched and identifies a median haul cycle time to allpossible truck dump locations. A percentage of the median time is addedto the median in order to provide a time period within which the truckshould be expected to complete a haul cycle i.e., dumping another load.For example, if the median haul cycle were 12 minutes and the centralcomputer 155 is programmed to add 20% to this time, if dump data werenot registered as being downloaded from this truck within this 12minutes+20%, the central computer then would flash to its operator thatthe truck in question is late in completing its haul cycle to a dumparea; whereupon, the operator of the central computer 155 may viaconventional two-way radio the truck's driver to see if there is aproblem with the truck.

If a truck driver parks the truck for a break or a rest stop, the driveralerts the operator of the central computer 155 to that fact viaconventional two-way radio. In response to this received data, theoperator of the central computer 155 punches up that truck number andindicates that truck's location and that no loads will be hauled for apredetermined time period and that possibly no data transmissions willbe occuring over this same time period. (Trucks should only be parkedwithin range of repeater 160a or 161). In some cases it is possible tocommunicate the same information via data downloaded through aninterrupt instituted by the operator's selection of an appropriate keyof the keyboard 122.

When a truck goes out of service because of a breakdown, operator restor the like, the central computer 155 dispatches new available trucks tothe loading area previously transmitted to the parked (on break) truckand then transmits to the parked truck a new updated loading location.This procedure is repeated until the parked (on break) truck isindicated as being back in service by data indicating such things as theshifting of gears. If the truck was loaded when parked, no dispatchingmay occur since the central computer 155 recognizes the truck is loadedand must be first dumped before it can be dispatched.

If no data has been received, at the end of the time period selected bythe truck operator as his break time or down time, the central computer155 will flash the truck number to the operator of the central computer.The central computer operator may radio, via conventional two-way radio,the truck to check on the truck's status. If the central operator findsthe truck is still down for whatever reason, he may punch up the trucknumber and indicate how many more minutes the truck will be down. Thisprocess continues to be repeated by the central computer 155 until thetruck is back in service or temporarily taken out of service.

With respect to truck travel from the dump area to a loader, the centralcomputer 155 records the time of truck dispatch and looks for that truckto arrive at the designated loading area within a predetermined timebased on historical truck return time in a primary data file. If thetruck is late in arriving at its designated loading area, i.e., no datadownloading to indicate arrival, the truck number is flashed to theoperator of the central computer whereupon he may radio, viaconventional two-way radio, the truck driver to check on that truck'sstatus.

The central computer 155 also follows the foregoing steps when itdetects a truck leaving a loading area headed for a designated dumparea. The central computer 155 identifies in its data file the averagehaul travel time it takes a like truck to get to the designated dumpingarea. If further data is not detected by the central computer 155 withinthis average time, then that truck number is flashed to the operator ofthe central computer whereupon he may check on that truck's status.

In addition to receiving downloaded data, monitoring and dispatchingtrucks 11 in the foregoing manner, the central computer 155 alsoidentifies and monitors the various loaders 160 by identifying therepeater 160a through which truck data is coming to the centralcomputer. Accordingly, the central computer 155, as data is downloadedto it, analyzes the average number of loads and/or tons loaded per hourby a particular loader 160 and how many minutes occur between each load.As the central computer 155 monitors each loader 160 through datadownloading, if it detects a lack of load information coming from aparticular repeater source, it flashes to the operator of the centralcomputer the number of that repeater source (or loader). The operator ofthe central computer 155 may radio, via conventional two-way radio tothe loader operator and identify whether there is a problem with theloader. If that particular loader 160 is down, the loader operator mayrespond to the operator of the central computer 155 with an estimate ofhow long he will be down. The operator of the central control computer155 then enters into the central computer that this loader will be downfor a particular time period.

The central computer 155 adds a percentage of this particular timeperiod to the estimated time period in order to provide a buffer range.At the end of this increased time period, the central computer 155checks the downloaded status of loader 160 and determines whetherloading data is present. If no loading data is present from this loader,the loader number is again flashed to the operator of the centralcontrol computer 155 whereupon he may again check with the operator ofthat loader to see how much longer it will be down. This additional timeis entered into the central computer 155 and the steps are repeated.

As soon as data is entered by the operator of the central computer 155indicating that a particular loader 160 is down, the central computerredispatches trucks 11 away from this loader with any trucks in theimmediate vicinity of that loader getting their signal through therepeater 160a on this loader while trucks in route may possibly have toarrive in the vicinity of the loader before picking up a redispatchnumber. For redispatching, the central computer 155 does not considerspecific travel times; rather, by way of simplification, it sets alltravel times equal for the loading locations to which the trucks areredispatched. This eliminates any data errors redispatching mightotherwise cause.

As a piece of loading equipment is down the time when that piece ofloading equipment is supposed to be back up is automatically registeredin the central computer 155 and the central computer, depending onprogramming, can automatically dispatch one and only one vehicle, or ifso programmed 2 or more trucks, to that piece of loading equipment. Or,if so programmed, the central computer 155 can flash the respectivenumber of the piece of loading equipment to the central computeroperator, whereupon he asks, via conventional two-way radio, the loadingequipment operator whether that piece of loading equipment is again upand ready to run so that trucks can be dispatched to it. If the answeris yes, trucks can be dispatched to that piece of loading equipment, theoperator of the central computer 155 enters in on his keyboard that,that particular piece of loading equipment is again up and running. Thecentral computer 155 then immediately takes over automatic dispatchingand dispatches the first available truck to that piece of loadingequipment.

If the central computer 155, through data being downloaded to it,determines there is either excess haulage capacity or loading capacity,it signals the computer operator. If excess haulage capacity isindicated, the computer 155 indicates which truck 11 is closest to arequired preventive maintenance period. A similar determination is madefor the loaders 160 when excess loading capacity is indicated. As soonas the excess truck 11 or loader 160 is identified and maintenancepersonnel are available, the central computer 155 dispatches theidentified truck or loader to the maintenance shop for preventivemaintenance work and/or notifies maintenance personnel to work on theloader 160.

With reference to equipment maintenance, if so desired by minemanagement, equipment maintenance can be incorporated with the sensorprocessing unit 101 and the central computer 155 data downloaded so thatas equipment maintenance occurs, equipment maintenance costs can beaccurately tracked, since the sensor processing unit 101 and the centralcomputer 155, via data downloading, will be tracking amount of equipmentoperating time, it will conversely be tracking equipment down time. Asdown time occurs, through the proper use of the operator number functionof the sensor processing unit 101 and data downloading from this unit toa central computer 155 with the operator number function, it is possibleto identify why a piece of equipment is down and through the proper useof operator number codes as well as when a piece of equipment goes backinto service, and as this data is generated for downloading to thecentral computer 155 via the operator number code on keypad 122, thecost of all parts and supplies used during the time that the truck isout of service can be entered directly into the central computer 155 viathe operator of the central computer, i.e., a truck is down fortransmission repair. The code for transmission repair is entered, viathe operator number code on keypad 122 into the sensor processing unit101 for data downloading, when the truck goes back into service, thecost of parts and supplies to repair the transmission is entered intothe central computer via the operator of the computer. If, however, theactual cost of the transmission repairs is not immediately known as atruck goes back into service, when they do become known, the operator ofthe central computer 155 can still enter the cost of parts and supplies,what they were for, and during what time period they were incurred sothat the central computer can go back and allocate for each period ofequipment down time as identified from data downloaded from sensorprocessing unit 101, the cost of repair parts and supplies associatedwith that segment of equipment down time.

From the foregoing it will be appreciated that the on-board weighingdevice provides the sensor processing unit 101 with raw data that can bedownloaded to a central computer for storage and analysis and then berefined to provide indications of truck and operator efficiency. Byanalyzing various mining parameters based on this downloaded raw data,the truck performance can be improved, thereby reducing the substantialcost of operating off-road, heavy duty trucks.

I claim:
 1. In a system of a plurality of vehicles, an apparatuson-board each of said vehicles for acquisitioning data indicative ofvehicle operation and for relaying said data to a remote control centerwhere the data is processed to create control signals that are deliveredback to said apparatus for instructing a vehicle operator regardingvehicle movement, said apparatus comprising:(1) means mounted to saidvehicle for indicating a loading of material into a dump body of saidvehicle by a loader; (2) means mounted to said vehicle for indicating adumping of a load carried by said body; (3) means mounted to saidvehicle for indicating a direction of movement by said vehicle;a firstprocessor means on-board said vehicle for acquiring data generated frommeans (1), (2) and (3) and processing said data for downloading to aremote control center; and (4) means for sending said processed data tosaid remote control center and for receiving control signals therefrom.2. An apparatus as set forth in claim 1 wherein said first processormeans includes (1) memory means for storing data indicative of apredetermined maximum weight capacity for said dump body, (2) detectionmeans responsive to incremental increases in a total weight of said dumpbody for determining an approximate weight of material added by a bucketof a loader, (3) comparison means responsive to said memory, firstprocessor and detection means for determining if said total weight minussaid predetermined maximum weight for said dump body is a fraction ofsaid approximate weight of material in said bucket, and (4) displaymeans responsive to said comparison means for indicating a remainingweight capacity of said truck body.
 3. An apparatus as set forth inclaim 2 wherein said detection means includes:means for detecting amonotonic increase in the total weight of said dump body; and means forstoring said increase.
 4. An apparatus as set forth in claim 2 whereinsaid display means includes a display of said remaining weight capacityof said dump body as a fraction of said approximate weight of materialin said bucket.
 5. An apparatus as set forth in claim 4 wherein saiddisplay means comprises a series of light indicators representative ofan approximate capacity of said bucket, said series of light indicatorsbeing relatively positioned such that each light indicator visuallyrepresents a fractional portion of said approximate weight of materialin said bucket.
 6. An apparatus as set forth in claim 1 wherein saidmeans (1) comprises a pressure sensor assembly mounted to a frame ofsaid vehicle for transferring from said dump body to said frame at leasta predetermined portion of a total weight of said dump body in asubstantially uniform manner along an interface between said frame andsaid dump body and said assembly is responsive to said predeterminedportion of said total weight to provide pressure data representative ofsaid total weight of said dump body.
 7. An apparatus as set forth inclaim 6 wherein said first processor means includes means for isolatingpressure data representing pressure spikes and means for recording theoccurrence of a pressure spike, and means responsive to said recordingmeans for delivering data to said display means indicative of acondition of a road over which said vehicle travels.
 8. An apparatus asset forth in claim 6 wherein said pressure sensor assembly includes acushioning interface between said dump body and said frame.
 9. Anapparatus as set forth in claim 6 wherein said dump body is pivotallymounted to said frame by way of a hinge assembly such that said pressuresensor assembly supports said total weight of said dump body in alowered position on said frame along an interface between said frame anddump body with none of said total weight of said dump body transferredto said frame via said hinge assembly.
 10. An apparatus as set forth inclaim 9 wherein said hinge assembly has body and frame portions and alsohas means for decoupling said body and frame portions when said dumpbody is moved to said lowered position such that said total weight ofsaid dump body is communicated to said frame through said pressuresensor assembly.
 11. An apparatus as set forth in claim 6 wherein saidpressure sensor assembly comprises at least one length of resilienttubing positioned on a beam of said frame wherein said resilient tubingprovides an interface between said dump body and said frame forcommunicating said at least predetermined portion of said total weightof said dump body to said frame.
 12. An apparatus as set forth in claim6 including:first transceiver means mounted to said vehicle; said firstprocessor means operatively coupled to said first transceiver means andsaid pressure sensor assembly for receiving said data from said pressuresensor assembly, processing said data and transmitting said processeddata by way of said first transceiver where said processed data includesan indication of a hauling status for said vehicle; and said remotecontrol center including a second processor means having a secondtransceiver means for communicating with said first transceiver means,said second processor means receiving said processed data from saidfirst processor means, said processed data identifying said vehicle andsaid hauling status of said vehicle derived from data from means (1),(2) and (3).
 13. An apparatus as set forth in claim 12 wherein saidvehicle may be loaded by any one of a plurality of loaders;said secondprocessor means includes (1) first means for calculating in response tosaid processed data an average load time for each of said plurality ofloaders, (2) second means responsive to said processed data and saidfirst means for calculating a current load delay time for each of saidplurality of said loaders, (3) third means responsive to said secondmeans for identifying a one of said plurality of said loaders having aminimum load delay (4), fourth means responsive to said third means forforming data for transmission by said second transceiver means, saiddata for transmission identifying a particular one of said plurality ofvehicles and said one of said plurality of loaders with said minimumload delay; and said first processor means including fifth meansresponsive to said data received from said fourth means via said firsttransceiver for displaying to said vehicle operator of said particularone of said plurality of vehicles an identifier of said one of loaders.14. An apparatus as set forth in claim 12 wherein said pressure sensorassembly includes tubings which forms said interface between each ofsaid body and frame of said vehicle.
 15. An apparatus as set forth inclaim 12 wherein said second processor means includes memory means forarchiving said processed data from said vehicle.
 16. An apparatus as setforth in claim 12 wherein said first processor means generates saidprocessed data for transmission in response to said pressure data fromsaid pressure sensor assembly and data generated by means (2) and (3)which are indicative of whether said vehicle is dumping its load,beginning loading of a new load or in transit between load and dumpsites.
 17. An apparatus as set forth in claim 16 wherein said means (2)is a dump sensor and means (3) is a gear sensor and said first processormeans generates said processed data for transmission in response to datafrom a plurality of sensors on-board said vehicle including said gearand dump sensors.
 18. An apparatus as set forth in claim 12 wherein saidsecond processor means includes memory means for archiving saidprocessed data in response to vehicle identification and vehicle typedata included in said processed data, thereby forming a data base. 19.An apparatus as set forth in claim 18 wherein said data base formed bysaid processed data archived in said memory means is used by said secondprocessor means to generate said control data for controlling themovement of said vehicle.
 20. An apparatus according to claim 12including:said second processor means including memory means for storinga predetermined maximum load capacity for said dump body; and said firstprocessor means including means for determining a weight of said dumpbody from said pressure data of said pressure sensor assembly andincorporating said weight as part of said processed data; said secondprocessor means responsive to said processed data for (1) comparing saidweight with said predetermined maximum load capacity, and (2) generatingan output signal identifying said vehicle if said weight is greater thansaid predetermined maximum load capacity.
 21. An apparatus as set forthin claim 20 including means responsive to said first processor means fordisplaying said weight of said dump body in response to said firstprocessor means.
 22. An apparatus as set forth in claim 20 includingmeans in said second processor means for accumulating a total number oftimes said output signal indicating an overload of the vehicle isgenerated.
 23. An apparatus as set forth in claim 6 wherein said firstprocessor means includes:means for storing said pressure data acquiredfrom said pressure sensor assembly; means for comparing selectedpressure data in said storing means with other pressure data in saidstoring means to determine if said selected pressure data are pressurespike; means responsive to said comparing means for counting thepressure spikes; and means responsive to said counting means forproviding an indication of the condition of a road over which saidvehicle travels.
 24. An apparatus as set forth in claim 6 including:saidfirst processor means providing an indication of a load or dumpcondition of said vehicle in response to said pressure data from saidpressure sensor assembly; distance means for measuring the distancetraveled by said vehicle and providing said distance to said firstprocessor means so as to be incorporated into said processed data;storage means responsive to said processed data for storing a distancetraveled by said vehicle between said indications of load and dumpconditions and for storing a total weight of a load hauled by saidvehicle between said indications; and means responsive to said storagemeans for multiplying said distance traveled by said total weight hauledin order to provide a tons-miles record as part of said storage means.25. An apparatus as set forth in claim 24 including means for dividingsaid tons-miles record by a time interval between successive indicationsof said load and dump conditions, thereby providing an indication ofwear experienced by said vehicle.
 26. An apparatus according to claim 6including:memory means operatively coupled to said first processormeans; means coupled to said first processor means for entering anidentifier of said vehicle operator and for associating a portion ofsaid memory means with said identifier; said first processor meansresponsive to said pressure data for (1) providing said processed datawhich is indicative of vehicle performance and (2) routing saidprocessed data indicative of vehicle performance to locations withinsaid portion of said memory means associated with said identifier;detecting means responsive to said entering means for detecting changesin said identifier; and display means responsive to said detecting meansfor displaying said processed data indicative of vehicle performance insaid portion of memory means when a change of said identifier hasoccurred.
 27. An apparatus as set forth in claim 6 where said vehicleincludes front and back axles and said apparatus includes means formeasuring loads carried by said front and rear axles of said vehiclewherein said dump body is pivotally mounted to said frame so as to pivotbetween raised and lowered positions, said means comprising:(5) meansfor measuring a force of said dump body on said frame and providing dataindicative of said force; said first processor means responsive to saiddata from said means (5) and said pressure sensor assembly fordetermining a distribution of said weight of said dump body over saidfront and rear axles of said vehicle; and display means responsive tosaid first processor means for displaying portions of said weight ofsaid dump body carried by said front and rear axles.
 28. An apparatus asset forth in claim 27 wherein hydraulic cylinders connected between saidframe and dump body move said dump body between said raised and loweredpositions, said means (5) sensing pressures of hydraulic fluids in saidhydraulic cylinders.
 29. An apparatus as set forth in claim 27 whereinsaid first processor means includes means for locating a center ofgravity of said dump body.
 30. An apparatus as set forth in claim 27wherein said first processor means includes memory means storingpredetermined tare weights for said front and rear axles and said firstprocessor means including summing means for adding said portion of saidweight on each of said front and rear axles to the tare weight of eachof said front and rear axles in order to find a gross weight for each ofsaid front and rear axles.
 31. An apparatus as set forth in claim 6,including means for pivoting said dump body between raised and loweredpositions on said dump body,said pressure sensor assembly including aplurality of sensor elements and providing an interface between saidframe and dump body when said dump body is in a lowered position, saidplurality of sensor elements provides an indication of the total weightof said dump body and an indication of fore-and-aft weight distributionas well as side-to-side weight distribution of the load carried by thedump body; and said first processor means having means responsive tosaid plurality of sensor elements of said pressure sensor assembly fordetecting an imbalance of said weight carried by said dump body andsignaling said vehicle operator in response thereto.
 32. An apparatus asset forth in claim 6 wherein said body is pivotally mounted to saidframe for movement between lowered and raised positions and saidapparatus includes a distance sensor for providing data to said firstprocessor means indicative of truck movement, said first processor meansincluding means responsive to said distance sensor and to said pressuresensor assembly for providing an output signal when said vehicle moveswithout said dump body in said lowered position.
 33. An apparatus as setforth in claim 6 wherein said dump body is pivotable between raised andlowered positions and wherein said first processor means includes (1)memory means for storing a tare weight of said dump body, (2) meansresponsive to the lowering of said dump body onto said pressure sensorassembly for comparing said total weight of said dump body with saidtare weight in said memory means, and (3) means for indicating said dumpbody is not fully empty when said total weight of said dump body isgreater than said tare weight of said dump body plus a predeterminedconstant.
 34. An apparatus as set forth in claim 1 wherein said means(1) comprises a bi-state switch positioned in a recess of a bed of saiddump body so as to detect a presence of material carried in said dumpbody.
 35. An apparatus for processing data derived from a weight of aload carried by a body of a truck, said apparatus comprising:a truckframe including a hinge assembly for pivotally supporting said truckbody between raised and lowered positions; a pressure sensor assemblymounted to said frame for supporting an entire weight of said body inits lowered position and providing pressure data representative of saidentire weight of said truck body; a processor means for receiving saidpressure data and detecting a change in said entire weight of said truckbody and formulating data indicative of truck condition in response tosaid pressure data and its change; a distance sensor for providingdistance data to said processor means indicative of truck movement; andsaid processor means including first means responsive to said pressuredata for detecting said truck body raised off said pressure sensorassembly and second means responsive to said first means and saiddistance data for providing an output signal when said truck moves withsaid body raised off said pressure sensor assembly.
 36. An apparatus forprocessing data derived from a weight of a load carried by a body of atruck, said apparatus comprising:a truck frame including a hingeassembly for pivotally supporting said truck body between raised andlowered positions; a pressure sensor assembly mounted to said frame forsupporting a weight of said body in its lowered position and providingpressure data representative of said weight of said truck body; aprocessor means for receiving said pressure data and detecting a changein said weight of said truck body and formulating data indicative ofsuch condition in response to said pressure data and its change; andsaid processor means including (1) memory means for storing apredetermined tare weight of said truck body, (2) means responsive to alowering of said truck body onto said pressure sensor assembly after aload carried by said body has been dumped for comparing said weight ofsaid truck body with said tare weight in said memory, and (3) means forindicating said body is not fully empty when said weight of said body isgreater than said tare weight of said body plus a predeterminedconstant.
 37. An apparatus for determining a remaining weight ofcapacity of a body carried on a truck frame which is loaded with amaterial by a bucket of a loader and for indicating when a weight ofsaid material in a full average bucket is more than said remainingweight capacity of said body, said apparatus comprising in combination:atruck frame including a hinge assembly; a truck body pivotally mountedto said truck frame at said hinge assembly, said truck body beingpivotally movable on said frame between lowered and raised positions; apressure sensor assembly mounted to said frame for supporting a weightof said body in its lowered position and providing pressure datarepresentative of a weight of said truck body; a processor means forreceiving said pressure data and determining said weight of said truckbody, said processor means including;(1) memory means for storing dataindicative of a predetermined maximum weight capacity for said truckbody, (2) detection means responsive to incremental increases in saidweight of said truck body for approximating a weight of said materialadded by said bucket, (3) comparison means responsive to said weight,said predetermined maximum weight capacity and said weight of saidmaterial added by said bucket for determining said remaining weightcapacity of said truck body, and (4) display means responsive to saidcomparison means for indicating said remaining weight capacity of saidtruck body.
 38. An apparatus as set forth in claim 37 wherein saiddetection means includes;first means for detecting an increase in saidweight of said truck body; and second means for storing said increase.39. An apparatus as set forth in claim 37 wherein said processor meansincludes means for isolating pressure data representing pressure spikesand means for recording an occurrence of a pressure spike, and meansresponsive to said recording means for delivering data to said displaymeans indicative of a road condition.
 40. An apparatus as set forth inclaim 37 wherein said display means includes a display of a remainingweight capacity of said truck body as a percentage of said weight ofsaid material carried by said bucket.
 41. An apparatus as set forth inclaim 40 wherein said display means comprises a series of lightindicators representative of a volume capacity of said bucket, saidlight indicators being relatively positioned such that each lightrepresents a fractional portion of said volume capacity of said bucket.42. An apparatus as set forth in claim 37 wherein said pressure sensorassembly is also a cushioning interface between said truck body and saidtruck frame.
 43. An apparatus as set forth in claim 37 wherein saidpressure sensor assembly includes a support means mounted on said truckframe, said support means directly supporting said truck body on saidtruck frame when said truck body is in a lowered position, said supportmeans supporting said truck body in its lowered position in such amanner as to support an entire amount of said weight of said body alongan interface between said truck frame and body with none of said weightof said body transferred to said truck frame via said hinge assembly.44. An apparatus as set forth in claim 37 wherein said hinge assemblyhas body and frame portions and also has means for decoupling said bodyand frame portions when said truck body is moved to said loweredposition such that an entire amount of said weight of said truck body iscommunicated to said truck frame through said pressure sensor assembly.45. An apparatus as set forth in claim 37 wherein said pressure sensorassembly comprises at least one length of resilient tubing positioned ona beam of said truck frame wherein said resilient tubing provides aninterface between said truck body and said truck frame for communicatingan entire amount of said weight of said body to said frame when saidbody is in said lowered position.
 46. A system for minimizing a haulingtime for each of a plurality of trucks between load and dump sites, saidsystem comprising:a plurality of on-board weighing devices each mountedon one of said plurality of trucks for providing signals indicative of atruck's operation; a plurality of processor means each mounted to one ofsaid plurality of trucks and each processor means responsive to a one ofsaid plurality of on-board weighing devices for receiving said signalsfrom said one of said plurality of on-board weighing devices andprocessing said signals to provide data indicative of a hauling status;a plurality of first transceiver means each mounted to one of saidplurality of trucks for receiving said data indicative of a haulingstatus from said one of said plurality of processor means andtransmitting said hauling status data in association with additionaldata that identifies said one of said plurality of trucks; and a remoteprocessing center including second transceiver means for receiving saidhauling status and truck identifying data from said one of saidplurality of first transceiver means, said remote processing centergenerating a historical data base, containing said data indicative of ahauling status and indexed by said identifying data.
 47. A system as setforth in claim 46 wherein said on-board weighing device includes apressure sensor assembly mounted on the frame of the truck andsupporting the body of the truck uniformly along an interface betweenthe truck body and frame.
 48. A system as set forth in claim 46 whereina plurality of loaders are provided at said load sites for loading saidplurality of trucks; andsaid remote processing center includes (1) firstmeans for calculating in response to at least said data base an averageload time for each of said plurality of loaders, (2) second meansresponsive to at least said data base and said first means forcalculating a current load delay time for each of said plurality ofloaders, (3) third means responsive to said second means for identifyingone of said plurality of loaders with a minimum load delay time, (4)fourth means responsive to said third means for forming control data fortransmission by said second transceiver means, said control dataidentifying a particular one of said plurality of trucks and aparticular one of said plurality of loaders with said minimum load delaytime; and each of said plurality of processor means mounted to saidplurality of trucks includes fifth means responsive to said control datareceived by said first transceiver for displaying for said particularone of said plurality of loaders identified by said control data.
 49. Asystem as set forth in claim 46 wherein said pressure sensor assemblyincludes tubings which forms the interface between each of said body andframe of said trucks.
 50. A system as set forth in claim 46 wherein saiddata base comprises a memory means responsive to said remote processingcenter for archiving said hauling status and identifying datatransmitted from said plurality of trucks.
 51. A system as set forth inclaim 46 wherein said processor means generates hauling status data fortransmission in response to said signals from said pressure sensorassembly which are indicative of whether a particular one of saidplurality of trucks in dumping its load, beginning a loading or intransit between load and dump sites.
 52. A system as set forth in claim46 wherein said remote processing center includes memory means forarchiving said hauling status and identifying data from each of saidplurality of processors in groups such that said data base is firstlyidentifiable with individual ones of said plurality of trucks andsecondly identifiable with types of trucks comprising said plurality oftrucks.
 53. A system as set forth in claim 52 wherein said remoteprocessing center is responsive to the said data base formed by saidhauling status and identifying data archieved in said memory means togenerate control data for controlling the movement of said plurality oftrucks by causing said second transceiver to transmit said control datato said plurality of first transceivers.
 54. A method for detecting andrecording a degree of road roughness for a truck having a body supportedon a frame,said method comprising the steps of:periodically calculatinga value of a force derived from a weight of said truck body on saidtruck frame; storing said value so as to accumulate a plurality ofstored values; periodically comparing a selected one of said pluralityof stored values with other of said plurality of stored values todetermine if said one of said plurality of stored values is a spikewherein said spike is a stored value that is greater than said other ofsaid plurality of stored values by a predetermined amount; accumulatingsaid spikes and providing a total count of said spikes; and derivingfrom said total count of said spikes an indication of the degree of roadroughness and displaying said indication.
 55. A method as set forth inclaim 54 wherein said force derived from said weight of said truck bodyon said truck frame is calculated with said truck body fully loweredonto said truck frame.
 56. A method as set forth in claim 54 whereinsaid force derived from said weight of said truck body on said truckframe is provided by a pressure sensor interfaced between the truck bodyand frane to communicate a predetermined portion of said weight of saidtruck body to said truck frame.
 57. A system for measuring a degree oftire use by a vehicle which hauls material in a dump body pivotallymounted to a frame of said vehicle, said apparatus comprising;distancemeans for measuring a distance traveled by said vehicle and providingdistance data; an on-board weighing device responsible to a weight of aload of said material hauled by said vehicle for providing (1) weightdata and (2) data indicative of a beginning and an ending of a haulcycle; storage means responsive to said distance means and said on-boardweighing device for accumulating said distance and weight data; andprocessor means responsive to said weight and distance data for (1) timemarking at least a portion of said distance and weight data so as toidentify an elapsed time of said haul cycle, (2) determining a totaldistance and a weight of said material for said haul cycle, (3)multiplying said total distance and said weight of said material forsaid haul cycle to provide a sum, (4) dividing said sum by said elapsedtime, and (5) displaying a value resulting from said multiplying means.58. An apparatus as set forth in claim 57 wherein said on-board weighingdevice includes a pressure sensor assembly mounted on said frame of saidvehicle which fully supports said weight of said load when said body ispivoted into a lowered position.
 59. An apparatus as set forth in claim58 wherein said body is pivotally mounted to said frame by way of ahinge assembly such that said body is fully supported by said pressuresensor assembly when said truck body is in said lowered position.
 60. Anapparatus for use in connection with an off-road, heavy-duty truckwherein said apparatus records vital statistics of said truck inconnection with an identifier entered into said apparatus by a truckoperator, said apparatus comprising:a processor means including memorymeans; means coupled to said processor means for entering saididentifier and associating a first portion of said memory means withsaid identifier; measuring means for providing signals indicative of ahauling status of said truck to said processor means; said processormeans responsive to said measuring means and said entering andassociating means for (1) receiving said signals, (2) providing dataindicative of truck performance in response to said signals and (3)routing said data to locations within said first portion of said memorymeans; detecting means responsive to a change of said identifier tocause said entering and associating means to associate a second portionof said memory means with a new identifier resulting from said change ofsaid identifier; and said processor means responding to said associatingof said second portion of said memory means with said new identifier byrouting said data to locations within said second portion of said memorymeans.
 61. An apparatus as set forth in claim 60 wherein said truck hasa body pivotably mounted on a truck frame, said measuring meansincluding:a pressure sensor assembly supporting an entire weight of saidbody on said truck frame when said body is in a fully lowered positionand said pressure sensor assembly providing pressure data representativeof said weight of said truck body; and said memory means including dataindicative of a predetermined maximum weight for said truck body.
 62. Asystem for identifying an overload condition in an off-road, heavy-dutytruck having a body mounted to a truck frame by a hinge assembly formovement between lowered and raised positions, said apparatuscomprising, in combination:a sensor assembly mounted on said truck frameand supporting a predetermined portion of a weight of said truck body onsaid truck frame when said truck body is in said lowered position, saidsensor assembly responding to said weight of said body to provide asignal indicative of said weight of said body; a means for transferringsaid signal to a remote, off-board processor means; said remoteoff-board processor means responsive to said signal and including memorymeans for storing a predetermined maximum weight capacity for said truckbody; and said remote off-board processor means responsive to saidsignal from said sensor assembly indicative of said weight for comparingsaid weight with said predetermined maximum weight capacity, and forgenerating an output signal if said weight indicated by said signal isgreater than said predetermined maximum weight capacity.
 63. A system asset forth in claim 62 including means for displaying said weight of saidtruck body.
 64. A system as set forth in claim 62 including means insaid remote off-board processor means for accumulating a total number oftimes said output signal is generated.
 65. An apparatus for measuringand manipulating various hauling and loading parameters for an off-road,heavy duty truck having a body, a frame and front and rear axles, saidapparatus comprising:a first weighing device on said truck for measuringa first force of said truck body on said truck frame and providing datarepresentative of said first force; a second weighing device on saidtruck for measuring a second force of said truck body on said truckframe and providing data indicative of said second force; a processormeans responsive to said first and second weighing devices fordetermining a fraction of a total weight of said truck body over saidfront axle and a fraction of said total weight of said truck body oversaid rear axle of said truck; and display means responsive to saidprocessor means for displaying said fractions of said total weightsupported by said front and rear axles.
 66. An apparatus as set forth inclaim 65 wherein said truck frame includes a hinge assembly and saidtruck body is pivotally mounted to said truck frame at said hingeassembly such that said truck body is pivotable between raised andlowered positions, said first weighing device supporting the entireweight of said truck body when said truck body is in its loweredposition.
 67. An apparatus as set forth in claim 66 wherein hydrauliccylinders connected between said truck frame and body move said truckbody between said raised and lowered positions, said second weighingdevice sensing a pressure of hydraulic fluid filling said hydrauliccylinder.
 68. An apparatus for measuring and manipulating varioushauling and loading parameters for an off-road, heavy duty truck havinga body, a frame and front and rear axles, said apparatus comprising incombination:hinge assemblies pivotally joining said truck frame andbody; a sensor assembly mounted on said truck frame and including aplurality of sensor elements, said sensor assembly supporting apredetermined portion of a weight of said truck body when said truckbody is in a lowered position on said truck frame; said sensor assemblyproviding an interface between said truck frame and body when said bodyis in said lowered position such that said plurality of sensor elementsprovides an indication of said weight of said truck body and anindication of fore-and-aft and side-to-side distribution of said weightof said truck body; and processor means responsive to said sensorassembly for detecting an imbalance of said weight carried by said truckbody and signalling a truck operator in response thereto.
 69. Astationary platform scale for placement on an approximately level groundsurface, said scale comprising, in combination:a first planar plate; aplurality of flexible tubing laid on said first planar plate with eachtubing having first and second ends; a second planar plate positioned torest atop said plurality of flexible tubing, said second planar plateextending to fully cover said plurality of flexible tubing; a pluralityof pressure sensors each secured to one of said first or second ends ofeach of said plurality of flexible tubing for providing pressure dataindicative of a weight present on said second planar plate; said secondplanar plate having a lower surface for direct contact with each of saidplurality of flexible tubing wherein said lower surface includes acalibration plate to ensure a known surface area of contact between saidplurality of flexible tubing and said second planar plate; and means forgathering all the data from said plurality of pressure sensors anddetermining a weight present on said second planar plate.
 70. Astationary platform scale as set forth in claim 69 includingstablization means coupling said first and second planar plates toretard movement parallel to the planes of said plates whilesimultaneously allowing the plates to move relative to one another in adirection normal to the planes of said plates.
 71. In a system forcontrolling a routing of a fleet of vehicles composed of distinct groupsto a plurality of possible locations, a method for monitoring andcommanding vehicle movement comprising the steps of:sensing a weight anda change in said weight of a load carried by each vehicle andformulating data representative of said weight and said change inweight; transferring said data to a central location; cataloging at saidcentral location said data from each vehicle; selecting one of saiddistinct groups of vehicles; combining said data from said one of saiddistinct groups of vehicles to provide collective data indicative ofgroup performance; and analyzing said cataloged and collective data toprovide commands for transfer to selected vehicles in said fleet ofvehicles.
 72. In a system for controlling a routing of a fleet ofload-carrying vehicles composed of distinct groups to a plurality ofpossible locations, an apparatus for monitoring and commanding vehiclemovement comprising, in combination:first means on-board each of saidvehicles in said fleet of vehicles for sensing a change in a loadcarried by said vehicle and forming data representative of said change;second means on-board each of said vehicles for transmitting said data;a central computer for receiving said data from each of said vehicles insaid fleet of vehicles and (1) cataloging said data to provide averagesfor each of said vehicles, (2) analyzing said averages from each of saidvehicles and (3) forming control data in response to said analysis thatincludes identification data identifying at least one vehicle in saidfleet of vehicles; and transmitting means coupled to said centralcomputer for transmitting said control data to a vehicle identified bysaid identification data.
 73. In a system as set forth in claim 72including repeater transmitters strategically located along routes ofsaid fleet of vehicles and each of said repeater transmitters receivingsaid data from vehicles in its vicinity and retransmitting said data tosaid central computer such that said retransmitted data identifies saideach repeater transmitter, thereby providing an approximate location ofeach vehicle in said fleet of vehicles.
 74. In a system as set forth inclaim 72 wherein said control data includes data designating sites forloading and dumping loads carried by said fleet of load-carryingvehicles and each vehicle in said fleet includes a display meansresponsive to said control data for displaying said designated sites toa vehicle operator.
 75. In a system as set forth in claim 72 whereineach vehicle in said fleet of vehicles is loaded with material by aloader and said data from said first on-board means provides anindication of the operation of said loader;said central computerincluding means responsive to said data for providing a quantitativeindication of an efficiency of said loader.
 76. In a system as set forthin claim 72 wherein each vehicle in said fleet of vehicles includes apivotal body mounted on a frame for movement between raised and loweredpositions and said first on-board means includes a pressure sensorassembly mounted to said frame for supporting a weight of said body insaid lowered position.
 77. In a system as set forth in claim 76 whereinan interface is formed where said pivotal body meets said frame, saidpressure sensor assembly is mounted on said frame such that saidpressure sensor assembly extends continuously along said interface whensaid body is moved to said lowered position.
 78. In a system as setforth in claim 72 wherein said first on-board means includes means fordetecting an increase in said load carried by said vehicle.
 79. In asystem for controlling a routing of a fleet of trucks composed ofdistinct groups to a plurality of possible locations and including acentral computer for receiving data from said trucks and issuingcommands to said trucks, said trucks having a dump body pivotallymounted to a frame, an apparatus on-board each of said truckscomprising, in combination:a pressure sensor assembly mounted to eachtruck in said fleet of trucks for providing pressure data indicative ofa weight of said dump body; a processor means on-board each of saidtrucks for receiving said pressure data and detecting a change in aweight of said body, and providing output data indicative of a truckoperating condition; and transmitter means on-board each of said trucksfor receiving said output data from said processor means andtransmitting said output data to said central computer for furtherprocessing.
 80. In the system set forth in claim 79, said centralcomputer including means for receiving said output data and formulatinga data base for each truck and each group of trucks, said centralcomputer also including means responsive to said data base for providingcontrol data to a second transmitter means operatively coupled to saidcentral computer.
 81. In the system set forth in claim 80 a receivermeans on-board each of said trucks for receiving said control data anddelivering it to said processor means.
 82. In the system set forth inclaim 81, said processor means including means responsive to saidcontrol data to provide display data to an on-board display means foruse by a truck operator.
 83. An apparatus for measuring a weight of aload carried by a body of a truck, said apparatus comprising, incombination:a truck body and a truck frame; means for coupling said bodyto said frame to inhibit side-to-side or fore-to-aft movement of saidbody with respect to said frame but allowing limited non-rotatingvertical movement; and a pressure sensor assembly supporting apredetermined portion of a weight of said body along an interfacebetween said body and frame such that a weight of said body istransferred to said frame uniformly along said interface.
 84. Anapparatus as set forth in claim 83 wherein said pressure sensor assemblyincludes a signal output indicative of pressure and said apparatusincludes a processor means for receiving said signal output.
 85. Anapparatus as set forth in claim 84 wherein said processor means includesmeans for detecting a change in said weight of said truck body andformulating data indicative of said truck condition in response to saidpressure data.
 86. A system for automatically measuring a weight of avehicle body and automatically transferring a measurement of said weightto a remote stationary site, said system comprising, in combination:avehicle frame for supporting said body; a pressure sensor assemblymounted on said vehicle frame and positioned along an interface betweensaid vehicle body and frame for supporting a predetermined portion ofsaid weight of said vehicle body such that said assembly distributessaid predetermined portion of said weight of said vehicle body in asubstantially uniform manner along said interface, said assemblyproviding at least one output signal indicative of a pressure at saidinterface between said body and frame; means remote from said vehiclefor receiving said at least one output signal and formulating anindication of said weight of said body; and coupling means joining saidpressure sensor assembly and said remote means for automaticallytransferring said at least one output signal from said assembly to saidremote site.
 87. A system according to claim 86 wherein said at leastone output signal from said pressure sensor assembly is fluid underpressure and said remote means is a pressure responsive device forproviding a visual indication indicative of said weight of said body andsaid coupling means is a conduit for communicating said fluid underpressure from said assembly to said pressure responsive device remotefrom said vehicle.
 88. A system according to claim 86 wherein said atleast one output signal from said pressure sensor assembly is anelectrical signal and said remote means is a circuit responsive to saidelectrical signal when received via said coupling means.
 89. A systemaccording to claim 88 wherein said pressure sensor assembly comprisesliquid-filled tubing.
 90. In a system utilizing pressurized tubing, anapparatus for terminating an end of said tubing and for insuring thetermination is leak-proof under high pressures, said apparatuscomprising, in combination:an end clamp located at said end of saidtubing and comprising first, second and third portions; said thirdportion of said end clamp located inside said tubing while said firstand second portions fit over an outside surface of said tubing and oposeone another so as to sandwich said tubing and third portion between saidfirst and second portions; means for joining said first, second andthird portions of said clamp with said tubing so as to totally seal theend of said tubing; and a collar surrounding said tubing at an areaproximate said end of said tubing but rearward of said end clamp, saidcollar having a central bore for receiving said tubing and restrainingsaid tubing from changing its cross-sectional shape in an area of saidtubing under and adjacent to said collar.
 91. In a system for monitoringhauling parameters of a vehicle with a dump body that pivots betweenraised and lowered pivotal positions, an on-board apparatus comprising,in combination:a sensor mounted on said body and responsive to thepivoting of said body for providing an output signal indicative of saidraised or lowered positions of said body, said sensor being totallyencapsulated in a housing in order to prevent ambient conditions fromreducing the responsiveness of said sensor; a processor for receivingsaid output signal from said sensor and responding to said outputsignals in a predetermined manner; and means communicating said outputsignal from said sensor to said processor wherein said means includes anoutput port in said housing which maintains said sensor in isolationfrom an ambient environment.
 92. The on-board apparatus as set forth inclaim 91 wherein said sensor is a mercury switch.
 93. In a system forcontrolling a routing of each vehicle in a fleet of material-haulingvehicles to one of a plurality of possible load or dump locations, anapparatus for monitoring and commanding vehicle movement comprising, incombination:means on-board each of said vehicles for providing anindication of a beginning of a loading of material into said vehicle anda dumping of said material from said vehicle and, in response to saidindication, forming data indicative of said loading or dumping; firsttransceiver means on-board each of said vehicles for transmitting saiddata; a central computer having a second transceiver means for receivingsaid data from each of said vehicles and having a processor and a memoryfor formulating from said data a data base from which control data isderived, said central computer including means for transmitting saidcontrol data to said vehicles, said control data including dataidentifying a particular vehicle and a particular one of said pluralityof possible load or dump locations; and said first transceiver meansreceiving said control data and said on-board sensing means respondingto said control data to visually indicate said particular one of saidplurality of possible load or dump destinations on an on-board displaymeans.
 94. An apparatus on-board a vehicle, being one of a plurality ofsimilar vehicles, for acquisitioning data indicative of vehicleoperation and for accumulating said data, said apparatuscomprising:first means mounted to said vehicle for providing dataindicative of a loading of material into a dump body of said vehicle anda dumping of said material by said dump body; second means mounted tosaid vehicle for providing data indicative of a movement of saidvehicle; a first processor means on-board said vehicle for acquiringsaid data from said first and second means and organizing said data toprovide information regarding performance of said vehicle; and a storagemeans for receiving said data from said first processor means andstoring said data as organized by said first processor means.